While e-sword is the best free software for Windows, the best free software for Android is MySword (unrelated developers).
The best free software for tablet Bible study is MySword. It is easy to use, supports many free Bibles (such as the KJV, the Majority Greek, the Critical Greek, the Septuagint, etc), hosts a good variety of commentaries, and includes various dictionaries. One of the best downloads is the Greek New Testament Byzantine with conjugations and declensions listed of all words:
2 Ἦσαν G1510 G5707 V-IAI-3P ὁμοῦ G3674 ADV Σίμων G4613 N-NSM Πέτρος G4074 N-NSM, καὶ G2532 CONJ Θωμᾶς G2381 N-NSM ὁ G3588 T-NSM λεγόμενος G3004 G5746V-PPP-NSM Δίδυμος G1324 N-NSM, καὶ G2532 CONJ Ναθαναὴλ G3482 N-PRI ὁ G3588 T-NSM ἀπὸ G575 PREP Κανᾶ G2580 N-PRI τῆς G3588 T-GSF Γαλιλαίας G1056 N-GSF, καὶG2532 CONJ οἱ G3588 T-NPM τοῦ G3588 T-GSM Ζεβεδαίου G2199 N-GSM, καὶ G2532CONJ ἄλλοι G243 A-NPM ἐκ G1537 PREP τῶν G3588 T-GPM μαθητῶν G3101 N-GPM αὐτοῦG846 P-GSM δύο G1417 A-NUI.
In the modern world, people no longer have to be able to know Greek to read it!