Periscope review: does Twitter's live-streaming service beat Meerkat?

This video app might be late to the party, but its extra features makes it worth the wait

It's fair to say that Periscope, Twitter's live-streaming video app, is late to the game. Not just the three-weeks-and-counting between its launch and that of tech press darling Meerkat, but the two and a half years between it and YouNow, which has grown to 100m user sessions every month by offering performers a share of the revenue.

So does Periscope have what it takes to seize the lead in an already crowded marketplace?