Bachus, I use Android I can do this... The best way I use MidiVoyager Pro.. This app allows me to load any sound font, or connect to any midi out device..

I can use the internal sound fonts and play live via my USB controller..

You can load individual fonts to the internal memory.. ..Latency is good.

I believe MidiVoyager Pro works with ipad too.. You might want to check it out..

https://play.google.com/store/apps/details?id=com.bytebolt.midiloops&hl=en_US