DS2.11 has been "reading" since shortly before 2.5. We have no idea how much he can actually read because he has significant speech delay but we know he can read a lot. He doesn't do it much in front of us but we hear him quite often when he's alone. The last month or so he has really started liking children's books on Kindle. He likes to listen to the stories being read to him and then tries it by himself. He is one of those "learn by osmosis" kids. He won't allow us to teach him anything. He has been recently diagnosed with High functioning autism (big part in it plays the speech delay) but we are still questioning it and are looking into possible Apraxia of speech. So it's really hard to tell what his reading level is, we just know he can read.
but aside from Starfall that has already been mentioned (and they have nice apps for Kindle as well as Android), if you have a Kindle, the children's stories might be good. We use a subscription to Kindle Free Time where for $2.99/ we get an unlimited access to a lot of apps and books that we would otherwise have to pay for.
