We used to advise people to do banking and other important business over their cellular connection when using a mobile device, since it is generally safer than connecting with a public Wi-Fi network. But even that isn’t always a safe bet. Researchers have demonstrated how a portable cell tower, such as a femtocell, can be used for malicious ends. The attack hinges on jamming the LTE and 3G bands, which are secured with strong encryption, and forcing devices to connect with a phony tower over the less-secure 2G band. Because the attacker controls the fake tower, they can carry out a man-in-the-middle attack and see all the data passing over the cellular connection. Admittedly, this is an exotic attack, but it’s far from impossible.
Wi-Fi attacks, on the other hand, are probably far more common than we’d like to believe. While attending the Black Hat convention, researchers saw thousands of devices connecting to a rogue access point. It had been configured to mimic networks that victim’s devices had previously connected to, since many devices will automatically reconnect to a known network without checking with the user. That’s why we recommend getting a VPN app for your mobile device to protect all your mobile communications. Even if you don’t have it on all the time, using a mobile VPN is a smart way to protect your personal information.
Most VPN services offer both Android and iOS VPN apps, saving you the trouble of configuring your phone’s VPN settings yourself. VPN providers typically allow up to five devices to be connected simultaneously under a single account. Also, while there are free VPN services available, many require that mobile users sign up for a paid subscription.
Not all mobile VPN apps are created equal. In fact, most VPN providers offer different services (and sometimes, different servers) for their mobile offerings than they do for their desktop counterparts.
If you’re of the iPhone persuasion, there are a few other caveats to consider for a mobile VPN. Some iPhone VPN apps don’t use OpenVPN, even if the VPN service that made the app supports the protocol. That’s because Apple requires additional vetting if a company wants to include OpenVPN with its app. VPN app developers have slowly started jumping through those extra hoops and are bringing support for protocols such as OpenVPN to iOS.
Thankfully, there’s a workaround for this problem. Instead of using the VPN app from the company from which you’ve purchased a subscription, you can download the standalone OpenVPN app. Open it, and you can enter your subscription information from the VPN company you’ve decided to work with. The OpenVPN app will then connect to the VPN company’s servers using our preferred protocol.