It seems the mobile app is no longer available for older Android versions (e.g. Android 4.2.x).
I find it handy to use a dedicated smart phone just for Mapillary. There is no SIM card and no other apps running therefore the battery will last longer. I have a microSD card where photos are stored. Moreover it won’t drain the battery of my main mobile phone.
I’m currently using this version I found in this forum:
It has some issues. It takes photo just for one hour then it crashes and sometimes it hangs during upload. But it is better than nothing.
I’ll try to contribute to Mapillary as long as my current setup works. After that… well… I guess that’s all folks!