Bass to iPad interface thingy

[Big J]

Whats the best option to get ? I play my bass through a couple of amp/combos but I’m moving with the times and getting an iPad for Xmas. What interface is best so I can plug the bass into the iPad (use some random software) and listen on headphones as I play? 
 Its a standard new iPad, not the new squared off one though (this is where I discover it has no output jack or something isn’t it....)

[paddy109]

I used a iRig with AmpliTube app. Cheap, although there might be better options available.

[AndyTravis]

I use an apogee jam+

works brilliantly - wish I’d bought a 2 input version really...but, does for the basslines and demos I send.

[Skybone]

Line6 SonicPort: https://line6.com/sonicport-audio-interface/sonicport/

[Woodinblack]

I use a line6 sonic port too. Stopped working for a while, but software update sorted that. probably means you can find a lot of cheap ones.

[Big J]

Cheers for the replies guys, I went for a sonic port vx. Only £25 second hand so it should be ok to try it out. 
jas