I carry adapters specific to the area I'm visiting. They're inexpensive and lightweight. I think they make multi-purpose adapters, but I prefer the simpler ones that just do one thing. 

For Tanzania, it looks like you need type G or D. You might want to take one of each - I've found that in countries with more than one type, it's hard to know which type a particular lodging will use. 

Also be aware that you'll need converters since they use 230 V and the US uses 120. Some of your devices already have converters. 

On our last trip, we took a big 10 USB hub with integrated converter, along with an adapter. It was enough for all the charging for 5 people - all 10 or so devices we felt necessary to bring with us :). We needed a separate adapter for the device (laptop) that didn't charge via USB.