This app was mentioned in 2 comments, with an average of 1.00 upvote
just fyi, The latest android versions have fixed the latency thing, so you can get amplitube for android now.
I haven't used it myself, though, so perhaps someone who has can say how well it works.
We created AmpliTube UA that runs on our device iRig UA that is coming in May and is on preorder now - AmpliTube UA was just released on Google Play yesterday (you can try the gear with the included audio demos until iRig UA is shipping). https://play.google.com/store/apps/details?id=com.ikmultimediaus.android.amplitubeua
Samsung Pro Audio was the only way to get good results for our apps like AmpliTube before this, and with the hardware solution the latency is reduced to below 2ms. For low-latency audio processing for app devs like us, it seems Samsung Professional Audio and now iRig UA are the only workable solutions for low-latency real-time audio processing on Android.