In some respects I feel like the Teenage Engineering OP-1 and pocket operators are taking over the spirit of the Roland 808. Easy to use but surprisingly deep hardware gear:
I really like the pocket operators. I have 3.
The PO-12 Rhythm is pretty awesome. The push buttons with lights is throwback to the 808 style of inputing rhythm.
There was a "808 emulator" (don't call it that wink..) for mac version (os 8) now iPad which I don't have. Though it doesn't say anything about roland in the description... You can see the 16 beats in a line with the led button. I will say I disliked the dial as a computer interface (works great physically, with a mouse not as well) and I haven't tried the iOS version..
Roland Fantom X user here. Those look pretty awesome! I had never heard of these instruments before now, glad you posted this. The OP-1 looks like the type of thing I'd been hoping to find as an affordable synth for a while.
https://www.teenageengineering.com/products/op-1