With tactics trainer, tactics tags, were just implemented earlier this year and many of those are being generated by users and voted on for accuracy. However, those aren't available during the problem, just after. It might be they will be available at some point on mobile apps, hopefully only as on option though.
That said, I always treat the tactics as I would an over the board position. I don't know what tactics are available in that situation; the benefit of a puzzle is you know something is there, you just have to figure it out.
First, I LOVE it!
Second, I like that it has the tactics trainer built in but you can't see what the objectiv is in the tactic being trained. Some tactics are to tatck the King. Some are to attack the Queen. Others are to rpeserve pieces. In the app (at least the iPhone app), it doesnt' say what the goal of each tactic is and sometimes (for newbie me), it's not obvious. I'd like to get that info as part of the iphone tactic trainer.
also, at least for me, my firends do not show up to challenge them under new online game--choose firend. My firend list is just empty there. I have to come to the site to start the game. Not a huge deal but I wish I could do it from there.