X-VPN
X-VPN is a popular free VPN with 'free forever' iOS and Android plans and downloads for Windows, Mac, Linux, Amazon Fire TV, and Chrome.
How popular? Google Play reports 10,000,000+ installs all on its own, and a 4.2 rating suggests the app's been doing something right.
X-VPN's website has some impressive features, including a large network of 8,000+ servers across 50+ locations, comparable with many of the top VPNs.