Ray there many pots here in Synthzone on this topic. Do a search.
1--I use Sweet Midi – Plays midi files with lyrics – it has a mixer allowing you to change tempo, change instruments and their volume, and transpose.

2—IrealPro – You write in the chord sequence. Very simple; I am able to create a song in 15 minutes; and there thousands of sequences available. Drums, bass, chords, style, tempo. It is not to be compared to something like Band-in-a-Box or a keyboard sequence, but it’s great for practicing a song, or a small crowd. Latin and Rock are fair; My kind of music – great.

3-IPad (Apple)(With WiFi) -- I bought the Apple product because they have an unbelievable amount of features and Apps.
I paid $356. I have used it for 3 ½ years.

John C.