SolForge is an interesting take on the digital card genre. It's a fairly simplistic card game, but with a suprising amount of depth / theorycrafting to your decks once you've unlocked some cards. It has the unique aspect of your cards levelling up as you play them; adding a depth of strategy that other card games haven't really explored. Not only do you have to think about what card to play right now, in order to damage your opponent, or save yourself from damage, but you also have to think about the future - and which cards you'll want then and how your deck will evolve compared to their deck.
The starter decks are playable, but I would strongly advise you to buy some packs (you can use silver which you can get from logging on daily and from winning matches) and get a custom deck going. You will get your ♥♥♥ kicked taking your cheap/free decks into PvP, but you can win your silver rewards playing against the AI - which is beatable on all difficulties with the starter decks, although the higher difficulties will be a challenge. If you do use real money to purchase packs, you will have a higher chance of getting the best cards, ultimately people should remember that card games are about spending money and RNG, but overall this is very playable as a free player too.
One of the big advantages of this game right now to me is that the Ipad app is extremely fluid and responsive. You can play untimed games with friends and the push notifications are accurate - meaning if you have a lazy day with 5 minutes to spare here and there, you can have a good duel with your friend from anywhere. (Untimed) games save despite the application being shut down; and you can start a game on the ipad and continue it on the PC, or have the game running in two locations at once if you so desire. A lot of digital card games right now have promised this sort of cross platform interactivity, but few have competently provided it yet. The android app is sadly not out yet so I can't comment on that - but they have said there'll be one in the future.
I'm pretty happy with it overall and would recommend.