This device is very popular on Play.com where it is one of the top sellers and it's received many rave reviews and statements like "battery lasts for ages" and "fantastic". Well I'm of a slightly different opinion.
Yes it's cheap, but it's built cheaply. The key ring itself is poor quality and needs adjusting with pliers to stop you losing the device at the first time out the house. The screen is grainy and lack lustre, with a strange fluctuation in brightness every few seconds on slideshow (on both units I bought). The menu is clunky to say the least, and the buttons on the back are slow to respond and hard to find the right one without looking. Why couldn't the "On" button be on the front or top, or anywhere that you can easily feel for it.
When you're in the menu then it's hard to navigate to the "Off" command, and that's the one you need the most. The reason for that is that if you inadvertently leave the unit on, then the next time you look at it the battery will be dead. I contacted the manufacturer and they quoted 4 hours life. What?..... 4 hours for such a tiny screen, I expected it would last days on end. The maximum time I've got out of it is about 6 or 7 hours, but even that is still less than a working day, and that means you need to be charging it up 3 times a day if you want to leave the slideshow on constantly.
There is an "Auto Off" menu item, but it only allows you to switch on the slideshow between certain times of the day, and not to sensibly turn itself off after a predetermined time (suggest 10 or 20 mins). I originally set the auto timer to come on at 8am and go off at midnight. It happily allows you to do this, but what the point when it won't last half that time!
I've searched through the specifications on all web sites (including the manufacturer's) and checked the packaging, but nowhere will it tell you the battery life. Well that's why I'm writing this review, to tell everyone that they admitted by email that it's only 4 hours, so when you buy this cheaply then be aware that you're getting a cheap device. I'd happily send mine back and buy one at twice the price if it lasted about 48 hours use between charges.