Opening Database for iphones

Just got a new iphone, and discovered that the opening database I've long used (called simply "openings") no longer exists and can't be downloaded to my new phone.

Are there other apps people recommend?

Obviously my version is for Android but im sure you can get it for i phone. I know it isn't technically a "database" but it references enough historical games and sidelines that it hopefully doesn't overload you, though certain openings its very very through. And there is puzzle practice positions for each opening as well taken i think from real games.

Thanks. Looked at it, and looks like a good resource but not quite what I’m looking for. What I really want is just a database of master games, preferably as large as possible. 

Lichess works fine except when you want to look at your own games. You can open a browser and try that but the lichess app is easiest to use

Check out Chess Studio by Giordano Vicoli. https://apps.apple.com/us/developer/giordano-vicoli/id460922805

ChessBase's ChessBase Online is no longer in the app store, although it still works for those of us who purchased it. You can get the same games in their online database, which also works on the iphone but works better if you have premium. https://database.chessbase.com

can't you just use the opening explorer on chess.com app? You have premium so it should be ok for you.

Thanks.  Chess Studio might be what I'm looking for.  Does it come with a database, or do I have to import one?  If it comes with one, how big is it? If not, how hard is it to import  a good one? (I'm not a technical whiz).

Is there a way to bookmark particular lines?  That would be helpful.

Lichess isn't a bad idea, though I'm not sure there's a way to bookmark lines, which would be ideal.

I'm not crazy about the opening explorer database because of the way it handles transpositions.  Essentially, it counts positions transposed to, rather than what was actually played from withing a given position, which can lead to absurdities like this:

https://www.chess.com/explorer?moveList=e4+f5&ply=2&origMoves=e4&ne=1

Which suggests that after 1. e4 f5, White almost never plays 2. exf5.

Wow

Okay, went with Chess Studio, but now I need a database for it. What do people recommend?

I don’t want to pay a lot of money but could pay some if there are good ones that are modestly priced. 

http://caissabase.co.uk/

Someone else had recommended caissabase, and I downloaded it.  Looks good. I even managed to convert it to a PGN file and upload it to google drive.  But I can't get it to upload from there to Chess Studio -- it doesn't recognize the link as a PGN file.  Am I missing some trick that's needed?  Is there another way?

just use openings101 website. there are a lot of theory and it's free.

I don't use Google drive so have no advice there. Chess Studio integrates with iCloud and Dropbox, so you might try one of those. In SCID I created a PGN and using the iOS Files app I copied it to the Chess Studio folder. But in Chess Studio the database icon has a red border. I tried to open it and the "Loading ..." splash spun for 45 minutes before I killed it. I didn't find any information on Chess Studio limits, but I suspect 5 million games and/or 3.2 GB exceeds those limits. It seems like your "as large as possible" database might need to be less than 2 million games and/or 2.0 GB to work at all in Chess Studio.

I was actually able to get it to upload but then got frustrated trying to figure out how to use it as a database once uploaded.  I gave up and really ought to get back to it.

What I want seems so simple, and really did exist until the app disappeared.  I could use one of the online databases (365chess isn't bad) except that I often use it most when offline (especially on the subway), so I'd love to make it just live on my phone like that one did.

Aargh.