On my old android device (Redmi Note 5A, Android 7.1.2) I faced the problem that the application crashes immediately after entering it. I got this exception in Android Studio:

E/AndroidRuntime: FATAL EXCEPTION: pool-3-thread-1
    Process: ru.spbu.depnav, PID: 3665
    java.lang.OutOfMemoryError: Failed to allocate a 4194316 byte allocation with 1130336 free bytes and 1103KB until OOM
        at dalvik.system.VMRuntime.newNonMovableArray(Native Method)
        at android.graphics.Bitmap.nativeCreate(Native Method)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:890)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:867)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:834)
        at ovh.plrapps.mapcompose.ui.state.TileCanvasState$special$$inlined$map$1$2.emit(Emitters.kt:224)
        at kotlinx.coroutines.flow.FlowKt__ChannelsKt.emitAllImpl$FlowKt__ChannelsKt(Channels.kt:62)
        at kotlinx.coroutines.flow.FlowKt__ChannelsKt.emitAll(Channels.kt:30)
        at kotlinx.coroutines.flow.FlowKt.emitAll(Unknown Source)
        at kotlinx.coroutines.flow.internal.ChannelFlow$collect$2.invokeSuspend(ChannelFlow.kt:123)
        at kotlinx.coroutines.flow.internal.ChannelFlow$collect$2.invoke(ChannelFlow.kt)
        at kotlinx.coroutines.flow.internal.ChannelFlow$collect$2.invoke(ChannelFlow.kt)
        at kotlinx.coroutines.intrinsics.UndispatchedKt.startUndispatchedOrReturn(Undispatched.kt:89)
        at kotlinx.coroutines.CoroutineScopeKt.coroutineScope(CoroutineScope.kt:264)
        at kotlinx.coroutines.flow.internal.ChannelFlow.collect$suspendImpl(ChannelFlow.kt:122)
        at kotlinx.coroutines.flow.internal.ChannelFlow.collect(ChannelFlow.kt)
        at kotlinx.coroutines.flow.internal.ChannelFlowOperator.collect$suspendImpl(ChannelFlow.kt:173)
        at kotlinx.coroutines.flow.internal.ChannelFlowOperator.collect(ChannelFlow.kt)
        at ovh.plrapps.mapcompose.ui.state.TileCanvasState$special$$inlined$map$1.collect(SafeCollector.common.kt:113)
        at kotlinx.coroutines.flow.FlowKt__ReduceKt.single(Reduce.kt:179)
        at kotlinx.coroutines.flow.FlowKt.single(Unknown Source)
        at ovh.plrapps.mapcompose.core.TileCollector$worker$1$bitmapForLayers$1$1.invokeSuspend(TileCollector.kt:135)
        at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
        at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
        at java.lang.Thread.run(Thread.java:760)
    	Suppressed: java.lang.OutOfMemoryError: Failed to allocate a 4194316 byte allocation with 1130952 free bytes and 1104KB until OOM
        at dalvik.system.VMRuntime.newNonMovableArray(Native Method)
        at android.graphics.Bitmap.nativeCreate(Native Method)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:890)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:867)
        at android.graphics.Bitmap.createBitmap(Bitmap.java:834)
        at ovh.plrapps.mapcompose.ui.state.TileCanvasState$special$$inlined$map$1$2.emit(Emitters.kt:224)
        at kotlinx.coroutines.flow.FlowKt__ChannelsKt.emitAllImpl$FlowKt__ChannelsKt(Channels.kt:62)
        at kotlinx.coroutines.flow.FlowKt__ChannelsKt.access$emitAllImpl$FlowKt__ChannelsKt(Channels.kt:1)
        at kotlinx.coroutines.flow.FlowKt__ChannelsKt$emitAllImpl$1.invokeSuspend(Channels.kt)
        		... 5 more

Troubleshooting was taken from here.

When a user scales out and more map area becomes visible, room markers become very distracting covering most of the screen area.

• [ ] Hide all unhighlighted markers when not zoomed in
• [ ] Keep only highlighted marker when one is present

Current Mathematics and Mechanics Faculty, SPbU map has several issues:

• Wrong building shape in a few places
• Missing elevators
• Missing scheme of the first floor of computational center

Google and other popular map apps have this double tap + slide zooming gesture: "One finger zooming by double tapping but not releasing on the second tap, and then sliding the finger up to zoom out, or down to zoom in" -- would be nice to also have this here.

Firstly, spbu-mm map now contains more objects, its structure is also more accurate. On the tiles, the rooms now look darker than the main passages.

Secondly, the database now has table constraints (foreign keys and uniqueness). For that marker_text table has been divided into a usual table and a separate virtual FTS table.

Thirdly, database queries have been modified to account for several maps. Adding new maps into the database should not break anything now.

Applies new MapCompose versions so that now gestures like zooming by double tapping and sliding and zooming out by tapping with two fingers are supported. Closes #31.

The new zoom fling feature is disabled for now as it is currently available only for zooming with two fingers (which feels inconsistent) and requires some tuning (speed needs to be reduced, it can be configured with MapState.configureGestures()).

• Adds repositories for abstracting database's DAOs
• Creates a single MainActivity with two screens instead of two activities
• Temporarily removes instrumentation tests from CI as the action used to run it stopped working for some reason (created a corresponding issue here)

Currently markers are lazy-loaded, but clustering seems to perform better.

• It can be optional (a switch setting between the current behavior and clustering can be provided)
• Clustering may be applied only to rooms, while other types of markers can use fade animation
• If a cluster only includes rooms from a single block (which have the same prefix) it can display this prefix (for example, if a cluster consist of rooms 2212, 2213, 2209 it may look like 22xx) -- this would require encoding marker blocks in their IDs

Mathematics and Mechanics Faculty at SPbU is divided into several parts, which is reflected in room names. It could be also reflected on the map somehow to help students get used to the internal organization of the faculty.

Add floating action button opening a menu of checkboxes using which a user would be able to pick only the markers they want to see. The categories to choose from are:

• Entrances
• Rooms
• Stairs and elevators
• Restrooms
• Other
• Closed