The 510's are really 3.2v, but there are 3.7v and 5v passthroughs that can be plugged into your computer or a wall adapter (you'd need a 2amp wall adapter to get true 5v's from a 510 5v passthrough, so just be aware of that). Just do a search on 510 passthroughs and do some reading.

The 808
batteries DO put out a true 3.7v. There are also many e-cig
mods available with any type of connection you can think of that do 3.7v, 5v, 6v or even variable voltage so you can pick the setting you like to vape at or change it to suit the
juice or atomizer you are using. There are passthoughs with 808 connections as well. Hope that helps.
