I had Plotagon on my old iPhone 4, it was okay and it had a few glitches. I downloaded it now (on my new phone) and it seems like all the bugs are gone! And the period of time between me getting a new phone was about 2-3 months! I really do recommend it and if you do find a bug please report so they can help fix the game!
CCGCRAZYCAT about Plotagon Story, v1.12.0