Apple talks a lot about privacy, but with Pegasus hitting the headlines, people are beginning to realise that the promises aren't as iron-clad as they thought.
A VPN won't help prevent such malware from attacking your iPhone, but what it will do is protect your privacy when you're online. For example your movements can be tracked by the websites you visit in Safari (or another browser) and your internet service provider can also see what you're up to, whether you're connected to Wi-Fi or using 3G, 4G or 5G.
Using a VPN can keep all this information private, preventing companies knowing what you buy, where you shop, what you watch, when you go to bed and where you're going on holiday.
It's important to note that using a VPN to get around geo-restrictions is usually against the terms and conditions of Netflix, BBC & Amazon.
While a VPN is new for many people, they are very simple apps to use and require no previous knowledge or technical expertise. It's as easy as launching the app, pressing the 'connect' button and then launching Safari or whichever other app you want to use.
Best iPhone VPN apps
NordVPN is a great all-round VPN service, offering super-fast speeds thanks to its 'NordLynx' protocol (based on WireGuard), lots of servers around the world and the fact that it's sensibly priced.
It's adept at unblocking popular video streaming services and will, of course, unblock websites that you can't otherwise access.
Nord's iPhone app looks great and is easy to use. You can have a list of your favourite servers for even faster connection, as well as configuring the app so it connects to the VPN when your phone joins an unknown Wi-Fi network.
The only missing feature is split-tunneling so you can't set it up so only specific apps use the VPN. But most people don't need to do that anyway.
NordVPN is based in Panama, an ideal territory for privacy laws. Plus it doesn't collect or store any information about how or when you use the service, so it would have no data to hand over even if authorities were to request it, which they won't. Better still, it has been audited recently to confirm that these aren't simply claims.
The service lets you connect to up to six devices at once and also has apps for iPad, Mac, Windows, Android and Amazon Fire TV.
If you subscribe for two years, you'll get a hefty discount, too.
Read our NordVPN review.
Sometimes you get what you pay for, but that adage can't be applied to VPN services - especially Surfshark. You might think it isn't as good because it's so inexpensive, but you'd be wrong.
There's a lot to like. Its iOS app has a slick, simple interface which makes it easy to pick from one of the 3200+ servers on offer. That's not far off double the 1700 or so the company had last time we looked at the service: it's constantly improving.
In fact, Surfshark has released new features on a regular basis, and is still one of few VPN services that offers two-factor authentication. It doesn't put any limits on the number of devices you can use simultaneously either.
It will unblock streaming services, just like NordVPN and has a few other handy features such as multi-hop which lets you route the connection through two VPN servers in different countries for another layer of privacy.
You can see the low price on Surfshark's website.
We also recommend reading our full Surfshark review for more details.
ExpressVPN is another excellent choice for your iPhone. As with the other services here, there are also apps for other popular devices, and you can use it on five of them at the same time, so it should cover the whole family.
As well as offering excellent security and privacy, it also unblocks more streaming services than its rivals, and there's friendly tech support available round the clock.
It's based in the British Virgin Islands for privacy reasons and, like Nord and others here, doesn't store any data about your use of its service.
It isn't cheap, though, costing over twice what many rivals charge per month.
The best deal is the 15-month subscription, which saves you 49% over the month-long option.
Read our ExpressVPN review.
As one of the longest-running, best-known VPN services, CyberGhost is another top choice for the iPhone - and other devices. The service is headquartered in Romania, which is outside the 14-eyes group of countries that share intelligence.
One of the great things about CyberGhost is its ease of use. It's particularly good for unblocking video streaming services (though it wouldn't let us watch BBC iPlayer or ITV Hub when we tried) and offers great connection speeds.
There are more than 6,700 servers available to connect to 88 different countries, as of July 2021.
So long as watching UK steaming services from abroad isn't top of your VPN wish list, Cyberghost is a fine choice.
Read our CyberGhost review.
VyprVPN is unusual in that it owns and operates all of its servers and network hardware. Most VPNs rent their servers, install their custom software and manage it remotely.
This is why VyprVPN is a great choice for privacy, and it also offers good speeds thanks to the recent introduction of WireGuard. It's also why there are fewer servers, but they're distributed among a good number of countries, and certainly those most people want.
It's speedy, thanks to WireGuard, and lets you have five devices connected at the same time.
As with its rivals, it operates a strict no-logs policy and offers deep discounts on the regular monthly price if you're willing to subscribe for a couple of years.
Find out more in our VyprVPN review.
PureVPN is notable not just because it offers more than 6,500 servers but because those servers cover a whopping 141 countries.
You're unlikely to need to pretend to be in most of them, but it could be a bonus if you do need to access something that's not in one of the commonly covered regions, or live in one of those countries and prefer a local server for the best speeds.
The new iPhone app, just like all PureVPN apps, has been given a total makeover and now looks bright and smart. More importantly, it makes it quick and easy to connect to your favourite locations, and it unblocks the stuff you want to watch.
And that includes - when we tested in April 2021 - iPlayer, ITV Hub and other UK services that others VPNs struggle with.
Ok, so it doesn't yet support WireGuard for blisteringly fast speeds - beyond most people's internet connection speeds - but it's more than quick enough for streaming video.
Install the app on your iPhone and you can get a seven day trial just by entering your email address. If you like it, then subscriptions are very reasonably priced.
Read our PureVPN review.
Ivacy isn't a free VPN service, but it's so cheap that it there's really no point in struggling along with the limitations of a free service.
And just because it's cheap doesn't mean it's no good. In fact, it's very good.
It can't match the very best services here for unblocking loads of video services - it wouldn't unblock Netflix Japan when we tested it in early 2021 - but it did work with the US library.
Click the link above and you'll see a five-year subscription deal. While that length of time might put you off, the up-front cost is about the same as many of the two-year deals here. So you're paying the same money (or less), but getting access for five years. If that's not convenient, we don't know what is.
As well as working on your iPhone, Ivacy has plenty of other apps and you can use up to five devices at the same time with the service.
It doesn't have the largest number of servers and you're not going to get the absolute top speeds, but the appeal here is value: it's a great service with minor niggles that you can read about in our full Ivacy review.