readable

(of handwriting, print, etc) legible, possible to read or at least decipher

“If that sign was still readable we'd know where we are!”

Which can be read—i.e. accessed or played—by a certain technical type of device

“No sale, those aren't readable with my DVD-player!”

(of a book) enjoyable to read, of an acceptable stylistic quality or at least functionally composed

“These assembly instructions aren't readable, I still don't have a clue how to start!”