Very advanced post/draft (written from a phone and unedited). Target audience: parents who coach their kids that have some computer experience (and little chess understanding), coaches, older/advanced students. I will revise this into a guide later.
TChess Pro is one of the first chess apps I ever purchased for an iPhone several years ago.
This is very similar to the thousands of chess apps out there, but I only use one special feature, that I can't find anywhere else: Analyze Game.
This feature automatically analyzes a game that you enter (beginners and intermediate players/parents can easily handle this).
Advanced chess students (or parents with computer experience) will prefer to import a PGN file via cut and paste. If you don't know what this means, that is normal! I recommend saving some games into Stockfish and emailing them to yourself to get a feel for what a PGN file is. A PGN file is basically a text file that has chess moves and player information. PGN is short for portable game notation.
Overall, going over games with a computer is a pretty advanced study routine. You have to have chess experience to understand computer feedback. This feature will only useful for players who have good habits of notating, entering their games, and most importantly, can read a graph.
The "read a graph" part is huge for me personally. I simply play a game, enter the moves via cut and paste, press Analyze Game, then look at the graph to see if I was ever winning. Or if I'm playing against an inexperienced player, I check to see if I am ever losing (people need to study their wins this way because winning is rarely done perfectly!).
Again, all this feature does is go over the whole game for you automatically, and creates a graph.
Right now, the only two chess apps I use are tChess Pro and Stockfish. I first enter a game into Stockfish and save it there. Then I click on the "send the game via email" option. In the newly composed email I see the pgn file. I cut and paste it, and immediately open tChess Pro. tChess pro automatically imports pgn files found on the clipboard.
t Chess Pro by Tom Kerrigan
Stockfish Chess by Tord Romstad