Could a developer with XCode performance tools run some tests and find any CPU burning code, background threads doing unnecessary work and so on, thanks? For a month or so Memrise has been very bad with battery lifetime, you use the app for 30 minutes and half of the battery or more is eaten up. I checked my battery lifetime status which is 90% and normal for a 2.2 year old iPhone with moderate use.
Anyway, compared with the other apps on my device Memrise’s battery consumption is off the charts just now.
This is just an intelligent guess but I think the iOS app is trying to talk to the back-end via the Wifi chip set quite a lot, burning up the battery lifetime. This is especially true if the wifi connection is spotty to bad or the back-end does not respond.
It would be better to have a staggered approach where the connection back to the back-end is delayed 2x each time, let’s say 1 minute, 2 min, 4 min, 8 min 16 min (max) until a good connection is again established and the algorithm is reset:ed. In addition it’s better to queue up changes for a bigger batch job periodically than try to update courses each time a course session is finished.