If you normally browse the web (and you don’t block ads), you’ve probably already seen hundreds, if not thousands, of advertisements for “VPNs” or “VPN software/subscriptions” — how you “need” one to have any kind of privacy, how “they”1 can track you everywhere if you don’t use one, and so on. And they’re usually not cheap. Interestingly, and probably because of some recent “revelations”, all those advertisements seem to focus on privacy or anonymity only.
But using a VPN can offer you something else: mobile security; namely, the ability to make your mobile devices “be”, on demand, part of your home network (or your server’s network, if you have, say, a VPS somewhere), no matter where you are, regardless of whether you’re using 3G/4G mobile data, or some random WiFi hotspot. Yes, even one with no encryption at all; it won’t matter. You can, absolutely, trust random open hotspots again; even their owner won’t be able to read or alter your traffic in any way. And you can do it for free, too (assuming you already have an always-connected Linux server); you just need to configure your own OpenVPN server, which you’ll be able to do by following this (hopefully accessible) guide.