[deltaqueue]

Almost all DSLRs and I assume many point-and shoots have an automatic focus tracking mode for moving subjects. Canon's is called AI servo. That said, most people don't move beyond the "auto" setting on their high-end cameras, so I can understand the quest to simplify.

Autofocus in smartphones will hopefully get better over time, but if your options are an overall superior DSLR or an equally large camera that just gives you some flexible (albeit one-dimensional) focusing benefits then I think the choice is clear. Practice a little more with your DSLR and wait to see if Lytro can be implanted into a better supporting cast of parts at a reasonable cost.

[apinstein]

I have a Canon T3i and 2 young kids. AI servo is the right idea in theory, but on even a lower-end DSLR it just doesn't help much. If a kid is running towards the camera, it will keep refocusing as the subject moves, but it's always focusing on where the kid was a split second ago.

IIRC the higher-end cameras have algorithms to track the subject and predict where the subject WILL be and focus accordingly. However, I have many friends with Mk III's and they say it's a very hard problem that even the high-end DSLR's don't solve. As you can imagine it's not actually a solvable problem with the present AF latencies as the subject can change course after the algorithm guesses. And when you're shooting shallow DoF even a small mistake will kill the focus on the shot.

The question is whether the Lytro can operate at 1/200 or faster to solve that problem. The specs say 1/4000 is max shutter speed, but IIRC the actual capture speed isn't that fast...