Understandable. Mobile games are becoming a little bit too time demanding for me right now. Between SIF EN/JP, Chain Chronicle, now this.. it would take like 15 minutes each morning to get rid of my LP in SIF alone. Bleh.
Yeah, for such small/simple games, they really can [and do] command a lot of your free time.
I only play School Idol Festival when there's an event going on [or when a new Story is added]. I'm Rank 149 in it, so it's not as though I need the XP. >_<
I also play Brave Frontier, but only casually. I don't spend my energy regularly, I mostly just log in for the free items and then quit. It's not as though there's a lot of content to work through in it. The same goes for Terra Battle and Puzzle & Dragons.
Monster Strike I do play, mostly farming Morling right now to max my units.
Chain Chronicle, though. This is the top in my current addition for iOS titles. I'll always log in ASAP and burn through all of my AP, clearing story quests, leveling my units, etc. Here's hoping we get another Demon Invasion soon, that last one was a lot of fun.