MapSwipe app crashing in certain projects

[kopitek8]

Issue

[Nicole to add more details]

Steps to Replicate

[Nicole to add more details]

Expected Behavior

[Nicole to add more details]

Actual Result

[Nicole to add more details]

Supporting Materials

[Nicole to add more details here like screenshot, project details, screen recording, etc.]

[nicolelaine]

Issue

When swiping in the "Finding buildings in Codajas - Amazonas - Brazil", when you get to the end of a group and you hit "continue mapping" occasionally the app freezes and crashes and it just says "loading" on the screen. The icon of the person with the magnifying glass is shown above the "loading" text. The only way out is to close the app completely and come back in. A work around is clicking on "end session" each time instead of "continue mapping" and then clicking "map now" on the main page of the project. This crashing only seems to happen in conjunction with the "continue mapping" button and only on this project (and some other projects in Brazil, where the GeoJSONs were made by the same person - these projects are now complete.

This issue is happening across at least two devices.

iPhone 12 mini
iOS 17.2.1

and

Fairphone 4
Android version: 13

Steps to Replicate
Go into the "Finding buildings in Codajas - Amazonas - Brazil" project on the app. Keep swiping and when you get to the end of the group, hit "continue mapping." Keep doing this until you see it crash. It does not happen consistently, so you might need to go through a few groups before it happens to you. Have patience! :)

Expected Behavior
Hitting "continue mapping" should cause the next tiles load properly and not hang on "loading."

Actual behavior
After hitting "continue mapping" the tiles hang with a "loading" text. The screen turns either blue or white with the MapSwipe icon above the loading text.

Supporting Materials

[kopitek8]

@nicolelaine

We have successfully replicated the issue and below are our findings:

The app hangs when:

• The screens are swiped consistently without any stop times
• The "continue mapping" button is clicked without any stop times not allowing the app to fetch data completely

The app does not hang when

• The screens are swiped as any normal user would do
• The app is allowed to fetch all necessary data before clicking the "continue mapping" button

We are still investigating as to why the issue seems to persist and have not found any concrete answers yet. More time is required for this issue.

A potential solution to the problem we have come up with so far is adding a 500ms (0.5 second) to 1000ms (1 second) of wait time before the user is allowed to hit the "continue mapping" button

[kopitek8]

While we have found the root cause for this issue, it now needs further research for implementation

[puranban]

• The app collects information from all tiles while the user is swiping
• The app sends the collected information to Firebase for further processing
• Now, firebase is stuck in a loop (in a PENDING state) which we have perceived as a crash

Potential solutions for this issue can be better error handling such as adding a timeout (could be 5 seconds) and adding a proper error message and redirecting to the initial screen