I find it works surprisingly well, as long as you're particularly careful about where you point it (as is necessary with any spot meter). While I was traveling in July, I found myself using it quite a bit when my 5-deg attachment for my Minolta Flashmeter III was giving me unreliable readings. I eventually sorted out the problem with my Flashmeter, but in the meanwhile, the Pocket Light Meter app was giving me reasonable readings.