there are a lot of very good games out on android, but, as usual, it absolutely depends on your personal taste.
For example, i really loved the old Final Fantasy games, especially FF Tactics. So i also like "Fantasy War Tactics" which looks and feels a lot like the old FF Tactics.
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However, if you never played / liked the old ones, you also won't like the new ones.
Another one i absolutely love is "Rayman Adventures", which is a platformer, not everyone likes these kind of games.
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Personally i'd say they both look stunning and have awesome soundtracks. But, as already said, that's just my opinion.
Aside from the big names there are always some little gems that never get the attention they'd deserve, like "Alto" for example.
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Or older games like "Beast Quest".
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Hell, even Kindom Hearts is available for android devices nowadays. Also, there is a big difference if you try to play some games on a normal smartphone to playing it on a tablet. Some games are literally unplayable on a small screen while other doing just fine.