A handful of Arc App users are reporting mysteriously high battery usage. Sometimes 10 or 20 times more than expected.

For the more extreme cases the users are seeing their batteries draining in a matter of hours. Normally Arc App and LocoKit can record entire days on a single battery charge, so for these particular users, something very wrong is happening.

My current best guess of the cause, based on user screenshots, is that for these users LocoKit is cycling between sleep and wake every few minutes, while stationary, instead of staying in sleep state until the user leaves their current location.

My hunch is the affected devices are producing a magical rare mix of low accuracy location data and slowly drifting location data, which could be somehow getting through LocoKitCore's filtering. Basically some poisonous combination of inaccurate location data while stationary that's slipping through the cracks and messing up sleep mode.

The problem is this never happens on any of my test devices, and is extremely difficult to properly debug remotely. So I need your help!

Are you experiencing this bug? Are you an iOS developer?

If so, I could really do with your help!

The best way to help is to install the LocoKit Demo App from this repo, and run it on the affected device in the affected location, and look for patterns.

The "LM" tab will hopefully be the most informative. Look for:

• Patterns in "Requesting accuracy" vs "Receiving accuracy"
• The number of locations in the "Latest sample"
• Incorrect changes in "Moving state"
• Drifting current location dots on the map
• A pattern of alternating short visits and short paths in the "TM" view while stationary

Note: You won't need an API key. I don't believe this bug is related to the ML classifiers at all.

Thanks for your help!

Hey, I'm having some trouble figuring out how to get the persistent store set up.

It seems like things might be working in localstorage, there is some level of persistence on the device in my simulator (e.g. when I print out Items, this persists from one session to the next). But I'm not seeing those show up in a database anywhere. I didn't see a ton of specifics on this in terms of what type of database to use and how to set it up. Any help would be much appreciated!

Here's my file where I'm initializing everything (also, fair warning, I come from a node.js background, so swift in general is all a bit new to me 😄)

Thank you in advance!

//
//  AppDelegate.swift
//  Joy
//
//  Created by Danny on 10/4/17.
//  Copyright © 2017 Joy. All rights reserved.
//

import UIKit
import LocoKit
import SwiftNotes

let appDelegate = UIApplication.shared.delegate as! AppDelegate

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
    
    var timeline: TimelineManager = PersistentTimelineManager()
    var store: PersistentTimelineStore = PersistentTimelineStore()
    
    var window: UIWindow?
    
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        LocoKitService.apiKey = "<REDACTED>"
        
        self.store = PersistentTimelineStore()
        store.dbUrl = URL(string: "<REDACTED>")!

        // the CoreLocation / CoreMotion recording singleton
        let loco = LocomotionManager.highlander
        
        // this is independent of the user's setting, and will show a blue bar if user has denied "always"
        loco.locationManager.allowsBackgroundLocationUpdates = true
        
        // retain a timeline manager
        self.timeline = PersistentTimelineManager()
        
        // restore the active timeline items from local db
        if let timeline = timeline as? PersistentTimelineManager {
            timeline.bootstrapActiveItems()
            print("bootstrapActiveItems ran....")
            
            // start recording, and producing timeline items
            self.timeline.startRecording()
        }
        
        // observe new timeline items
        when(timeline, does: .newTimelineItem) { _ in
            if let currentItem = self.timeline.currentItem {
                print(".newTimelineItem (\(String(describing: type(of: currentItem))))")
            }
            onMain {
                let items = self.itemsToShow
                print(items, "<<<<")
            }
        }
        
        // observe timeline item updates
        when(timeline, does: .updatedTimelineItem) { _ in
            onMain {
                let items = self.itemsToShow
            }
        }
        
        // observe timeline items finalised after post processing
        when(timeline, does: .finalisedTimelineItem) { note in
            if let item = note.userInfo?["timelineItem"] as? TimelineItem {
                print(".finalisedTimelineItem (\(String(describing: type(of: item))))")
            }
        }
        
        when(timeline, does: .mergedTimelineItems) { note in
            if let description = note.userInfo?["merge"] as? String {
                print(".mergedItems (\(description))")
            }
        }
        
        // observe incoming location / locomotion updates
        when(loco, does: .locomotionSampleUpdated) { _ in
            self.locomotionSampleUpdated()
        }
        
        // observe changes in the recording state (recording / sleeping)
        when(loco, does: .recordingStateChanged) { _ in
            // don't log every type of state change, because it gets noisy
            if loco.recordingState == .recording || loco.recordingState == .off {
                print(".recordingStateChanged (\(loco.recordingState))")
            }
        }
        
        // observe changes in the moving state (moving / stationary)
        when(loco, does: .movingStateChanged) { _ in
            print(".movingStateChanged (\(loco.movingState))")
        }
        
        when(loco, does: .startedSleepMode) { _ in
            print(".startedSleepMode")
        }
        
        when(loco, does: .stoppedSleepMode) { _ in
            print(".stoppedSleepMode")
        }
        
        when(.debugInfo) { note in
            if let info = note.userInfo?["info"] as? String {
                print(".debug (\(info))")
            } else {
                print(".debug (nil)")
            }
        }
        
        return true
    }
    
    var itemsToShow: [TimelineItem] {
        if timeline is PersistentTimelineManager { return persistentItemsToShow }
        
        guard let currentItem = timeline.currentItem else { return [] }
        
        // collect the linked list of timeline items
        var items: [TimelineItem] = [currentItem]
        var workingItem = currentItem
        while let previous = workingItem.previousItem {
            items.append(previous)
            workingItem = previous
        }
        
        return items
    }
    
    var persistentItemsToShow: [TimelineItem] {
        guard let timeline = timeline as? PersistentTimelineManager else { return [] }
        
        // make sure the db is fresh
        timeline.store.save()
        
        // fetch all items in the past 24 hours
        let boundary = Date(timeIntervalSinceNow: -60 * 60 * 24)
        return timeline.store.items(where: "deleted = 0 AND endDate > ? ORDER BY endDate DESC", arguments: [boundary])
    }
    
    func locomotionSampleUpdated() {
        let loco = LocomotionManager.highlander
        
        // don't bother updating the UI when we're not in the foreground
        guard UIApplication.shared.applicationState == .active else {
            return
        }
        
        // get the latest sample and update the results views
        let sample = loco.locomotionSample()
    }

    func showLoggedInView() {
        // initilize vc right away, otherwise flashes on launch
        let vc = UINavigationController(rootViewController: SummaryViewController())
        show(vc)
    }

    func showLoggedOutView() {
        let vc = OnboardingNavigationController(rootViewController: WelcomeViewController())
        show(vc)
    }

    private func show(_ vc: UIViewController) {
        window = UIWindow(frame: UIScreen.main.bounds)
        window?.rootViewController = vc
        window?.makeKeyAndVisible()
        window?.tintColor = .joyPurple
    }

    func applicationDidBecomeActive(_ application: UIApplication) {
        application.applicationIconBadgeNumber = 0
    }

}

I have many "Swift Compiler Error" in my project after installing it with CocoaPods (57).

I can't even build the LocoKit Demo App because it also gives me all of these errors.

This is the error I get when adding it to my project.

• 'collations' is inaccessible due to 'private' protection level (and many others of the same type)

These are the errors I get trying to build the LocoKit Demo app (20):

• Type 'ComplexArray' does not conform to protocol 'RangeReplaceableCollection'
• Ambiguous use of 'count'
• Type 'ValueArraySlice' does not conform to protocol 'Collection'

What am I doing wrong?

I've played a little with SDK (latest version, master branch). I'm testing it on my project which has NetworkLogger. (I use it to inspect network request, log specific info)
What I've found strange that my application using SDK executes tones of API requests for the same coordinates. I tried to change my location just by walking at the office. So I don't have significant location changes, just stationary. Also I use default accuracy options (30 meters). It might be better to add some throttling mechanism in order to reduce number of network requests for the same location.

Link for screenshot

iOS version: 11.4.1 Device: iPhone 6+ Xcode: 9.4.1 GPS/Wifi/CoreMotion is Enabled.

hello，i clone code About ‘ArcKit’ ，but couldn't run ，tips can‘t find ’ArcKit‘ ，try ’pod install‘ tips ’Unable to find a specification for ArcKit (= 5.0.0.pre)‘. how i can fix it, thx谢谢！！

Thank you for an awesome library, @sobri909!

I recently moved to using an M1 Mac as my daily driver - and, unfortunately, LocoKitCore.framework is not a happy camper. While building to device works, simulator build fails due to either a missing ARM64 version of the iOS 10 SDK or to Swift 5.1/5.3 incompatibilities - the error message is not particularly clear on that.

Attempts to build an app with LocoKit end up with the following error:

<unknown>:0: error: unable to load standard library for target 'arm64-apple-ios10.0'
[redacted]:10:8: error: failed to build module 'LocoKitCore' from its module interface; the compiler that produced it, 'Apple Swift version 5.1.3 effective-4.2 (swiftlang-1100.0.282.1 clang-1100.0.33.15)', may have used features that aren't supported by this compiler, 'Apple Swift version 5.3.1 effective-4.2 (swiftlang-1200.0.41 clang-1200.0.32.8)'
import LocoKitCore

Any chance you could rebuild the LocoKitCore.framework with the most recent Swift compiler and/or target a newer standard library? Happy to help out with debugging this if you don't have access to an Apple Silicon Mac!

Hello,

I've just added the develop branch as pod dependency using

pod 'LocoKit', :git => 'https://github.com/sobri909/LocoKit.git', :branch => 'develop'
  pod 'LocoKit/Timelines', :git => 'https://github.com/sobri909/LocoKit.git', :branch => 'develop'
  pod 'LocoKitCore', :git => 'https://github.com/sobri909/LocoKit.git', :branch => 'develop'

When building, I get this error in LocoMotionManager.swift:

It seems to be due to the fact that LocoKitCore framework hasn't been committed to the repo since a long time? Is it possible to build it from source?

My podfile is as below:

pod 'LocoKit', :git => 'https://github.com/sobri909/LocoKit.git', :branch => 'develop'
pod 'LocoKitCore', :git => 'https://github.com/sobri909/LocoKit.git', :branch => 'develop'
pod 'LocoKit/Timelines', :git => 'https://github.com/sobri909/LocoKit.git', :branch => 'develop'

And I got error: ../Pods/LocoKit/LocoKit/Timelines/ActivityTypes/ActivityTypesCache.swift:10:8: Module compiled with Swift 4.2 cannot be imported by the Swift 5.0 compiler: ../Pods/LocoKitCore/LocoKitCore.framework/Modules/LocoKitCore.swiftmodule/arm.swiftmodule

../Pods/LocoKit/LocoKit/Timelines/ActivityTypes/ActivityTypesCache.swift:10:8: Module compiled with Swift 4.2 cannot be imported by the Swift 5.0 compiler: ../Pods/LocoKitCore/LocoKitCore.framework/Modules/LocoKitCore.swiftmodule/arm64.swiftmodule

My project's swift language is 4.2, and pod is also 4.2. I already try this https://stackoverflow.com/a/46739102/5957749 but still not work at all......

👋 Hey Matt, anything else we should be cautious of when updating to Swift 4.2? Saw this thread https://github.com/sobri909/LocoKit/issues/20 and was successfully able to migrate to Swift 4.2.

iOS 12 Unfortunately with our existing build on the latest released version of LocoKit, we're experiencing weird/inaccurate location data on iOS 12. I saw this comment, looks like you were/are experiencing similar issues https://github.com/sobri909/LocoKit/issues/29#issuecomment-423201624

I'm seeing much higher rates of background fails in iOS 12 (in Arc's analytics, and on my test devices). And much higher rates of nonsense location data, with some devices "sleepwalking" on almost a daily basis, several kilometres away from where they really are.

Are you still seeing issues with LocoKit on iOS 12? Did Apple end up fixing some of their issues with the patch release? Anything I can potentially help with? (don't know how much time I have)

For what it's worth, I'm also experiencing quite a few crashes in the background on TimelineStore.save(). The app crashes after some time in the background. Anything potentially wrong with my setup or are you noticing the same thing? Any help is much appreciated, thanks.

0  libswiftCore.dylib             0x10143e480 _stdlib_destroyTLS + 207848
1  libswiftCore.dylib             0x101493f2c swift_unexpectedError + 280
2  LocoKit                        0x101064b10 TimelineStore.save() (TimelineStore.swift:325)
3  LocoKit                        0x101066858 closure #1 in TimelineStore.process(changes:) (TimelineStore.swift:348)
4  LocoKit                        0x100ff2a68 thunk for @escaping @callee_guaranteed () -> () (<compiler-generated>)
5  libdispatch.dylib              0x1db5c36c8 _dispatch_call_block_and_release + 24
6  libdispatch.dylib              0x1db5c4484 _dispatch_client_callout + 16
7  libdispatch.dylib              0x1db56bc18 _dispatch_lane_serial_drain$VARIANT$mp + 592
8  libdispatch.dylib              0x1db56c760 _dispatch_lane_invoke$VARIANT$mp + 432
9  libdispatch.dylib              0x1db574f00 _dispatch_workloop_worker_thread + 600
10 libsystem_pthread.dylib        0x1db7a60f0 _pthread_wqthread + 312
11 libsystem_pthread.dylib        0x1db7a8d00 start_wqthread + 4

It's too early to start on this one yet, but implementation ideas have been popping up in my head all week, so I might as well get them written down.

Misc random thoughts

1. Ditch the coords pseudo counts for transport types that are coordinate bound (eg car, bus, train, and any future road/track/etc bound types).

2. Only include types in the transport classifier that have non zero sample/coord counts for the D2 region, to avoid over stuffing the classifiers with possible types.

3. Look at ditching some model features, due to possibly being a negative influence. coreMotionActivityType is the most likely candidate for ditching, due to being wrong more often than right. Next would be courseVariance, due to being essentially meaningless for all types except stationary, since the introduction of the Kalmans.

4. Try letting zero step Hz back in for walking. There's certainly enough data for the models now, and phones are newer and smarter, so there's less risk of false zeroes, and more data to cope gracefully with those cases now too.

5. Look at deepening / broadening the composite classifiers tree. Could consider clustering all "steps" based types in a subtree (walking, running, cycling, horse riding, maybe skateboarding, others). Consider clustering the road bound types (car, bus, tram?). And there's the open question of whether a third depth would make sense in some cases, for when there's too many types to be sensibly clustered in a single classifier.

• Need to flesh out the storage model for user custom types. And for custom types that have the potential to being upgraded to shared types. Things like naming specific train lines, naming specific roads, etc. These might initially come in as custom user types, but there needs to be a privacy conscious, opt-in path to upgrading these to shared types, if it makes sense to do so.

I'll come back to this and add more thoughts over the next week or two. There's a bunch more details that have already crossed my mind, but I'm not remembering them right now...

I did a pod install for ArcKit which was successful, but when I build, I get the error:

“Swift Language Version” (SWIFT_VERSION) is required to be configured correctly for targets which use Swift. Use the [Edit > Convert > To Current Swift Syntax…] menu to choose a Swift version or use the Build Settings editor to configure the build setting directly.

I did this to upgrade to Swift 3.0, but it still fails to build. I also changed the build target to be iOS 10.3 instead of iOS 11, but still doesn't build. Is there anyway to fix this?

Thanks.

I just curious why use max of bins as divisor instead of sum of bins?

LocoKit/Timelines/ActivityTypes/Histogram.swift

    public func probabilityFor(_ value: Double) -> Double {
        guard let max = bins.max() else {
            return 0
        }
       
        // shouldn't be possible. but... 
        guard !binWidth.isNaN else {
            return 0
        }
        
        // single bin histograms result in binary 0 or 1 scores
        if bins.count == 1 {
            return value == range.min ? 1 : 0
        }
        
        let bin: Int
        if value == range.max {
            bin = bins.count - 1
        } else {
            let binDouble = floor((value - range.min) / binWidth)
            
            if binDouble > Double(bins.count - 1) {
                return 0
            }
            
            guard !binDouble.isNaN && binDouble > Double(Int.min) && binDouble < Double(Int.max) else {
                return 0
            }
            
            bin = binWidth > 0 ? Int(binDouble) : 0
        }
        
        guard bin >= 0 && bin < bins.count else {
            return 0
        }
        
        return (Double(bins[bin]) / Double(max)).clamped(min: 0, max: 1)
    }

Current CocoaPods published version is 7.0 (although I see 7.1 tagged here in github).

With Xcode 13 / Swift 5.5 am getting:

error: module compiled with Swift 5.1.3 cannot be imported by the Swift 5.5.1 compiler

Will you be providing a compatible update for the binary LocoKitCore ?

Thanks

Hi @sobri909, Please help me on deleting TimelineItems from db. I'm trying with tappedClear() function to delete items. but I'm not able to track that how many items are already delete from db, because immediate boolean in save() function is false.

 var dataSet: TimelineSegment?

 var itemsToShow: [TimelineItem] {
        return dataSet?.timelineItems ?? []
  }
    
  func tappedClear() {
        // TODO: flush the timeline data
        self.itemsToShow.forEach {
            $0.delete()
        }
        store.keepDeletedObjectsFor = TimeInterval(timerCount)
        store.hardDeleteSoftDeletedObjects()
    }
    
  public func save(_ object: TimelineObject, immediate: Bool) {
        mutex.sync {
            if let item = object as? TimelineItem {
                itemsToSave.insert(item)
            } else if let sample = object as? PersistentSample {
                samplesToSave.insert(sample)
            }
        }
        if immediate { save() }
    }

Hi Matt, I'm trying to fetch most recent "TimelineItem" and I'm getting it... but every time I'm getting activityType either stationary or nil. Please help me on this. Thanks in advance.

if let mostRecentItem = self.store.mostRecentItem { printDebug("=========================================") printDebug("item (mostRecentItem)") printDebug("item modeMovingActivityType (String(describing: mostRecentItem.modeMovingActivityType))") printDebug("item activityType (String(describing: mostRecentItem.activityType))") printDebug("item modeActivityType (String(describing: mostRecentItem.modeActivityType))") printDebug("item startDate (String(describing: mostRecentItem.startDate))") printDebug("item endDate (String(describing: mostRecentItem.endDate))") printDebug("item duration (mostRecentItem.duration)") printDebug("item stepCount (String(describing: mostRecentItem.stepCount))") }

FYI: while building the latest ArcMini, Xcode spit out the following warning:

found 1 file(s) which are unhandled; explicitly declare them as resources or exclude from the target
    .../DerivedData/Arc_Mini-dlenhigbcoeldyfxldburkutnfjk/SourcePackages/checkouts/LocoKit/LocoKit/Timelines/ActivityTypes/CoordinateBins.fbs

Not sure if this is a LocoKit or ArcMini issue.