I don't know why there are so many reviews about bugs, lags and high ping. At least the ones I've seen...
I started playing literally from the very opening of the servers and I only noticed a slight freeze and low fps sometimes. Not critical. I encountered only 1 bug and it was more amusing than critical too.
My phone is not so powerful by my standards, but I play on high settings and calmly play in 45fps or 30fps. (not really like playing in 60+ fps)
The gameplay is great, the music is great and the story is quite interesting. Don't forget that this is just the beginning and it will be better in the future. Too bad if you came not for a good game, but to say that the game has no future on the first day of its release.