Thought I should share this: should you be in need of an extended battery for most (not all) smartphones, you can get them from https://www.mugen-power-batteries.com/

I got one for HTC (the stock battery is 1300mAh, the extended is 1800mAh). So far the battery is working very well and it does retain charge for longer.

Shipping is free but dont buy from their site. Apparently they don't ship to Kenya coz things get lost in the local postal.

So I went and got it from Amazon for the same price and still with free shipping.

Note that it will take longer to ship using the free option. I created the order on Feb 2nd and it arrived at City Square posta on Feb 21.