[scorpion032]

The main app is optimized for reading your timeline. Fetches notifications, friends, messages etc.

It is hard to optimize for different tasks at once, while I'd also argue it would be possible to strike a good balance. But I think it is a pragmatic decision rather than try to achieve that perfect balance, and let several instagrams take over, do the right thing for each task and a year down the line knowing usage patterns, with much better hardware, you can think about a consolidated app.