We submit 65 smartphones per year to more than 40 tests as part of Which? testing laboratory to share our recommendations with you. After years of comparing hundreds of handset and SIM card deals, we know what makes a good one.

There will be an abundance of Black Friday phone deals, so follow our tips to get the best possible deal on your next device, whatever your budget. There are also simple steps you can take to care for your handset to keep it in better condition for longer and prevent your data from falling into the wrong hands.

Read on to learn the five things I would avoid doing as a phone expert.

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1. Buy a phone with a contract without calculating the total cost

Phone contracts can be a tempting way to spread the cost of your device instead of buying a phone outright (also known as buying SIM-free). However, what may seem like a reasonable monthly cost can mask the premium you pay overall. Long-term contracts may also be subject to mid-contract price increases, so your monthly cost will increase over time.

In almost all cases, I would buy a phone outright with a separate Sims-only deal to save money. But before I do that, I will do the math on all the deals I find to make sure this is the best way to go. To make this easier, you can use our contract calculator below.

2. Buy a phone that is too old

Buying a phone that is around a year old or buying a refurbished phone can save you a lot of money, especially when it comes to high-end phones from the likes of Apple, Samsung, and Google. Overall, the upgrades we’ve seen on phones over the past few years haven’t been anything special, so you’re not missing out on much by going back a generation or two. However, make sure the handset you’re looking at is still supported for updates. I would recommend choosing one with at least two years of updates remaining.

Software updates bring the latest features to your phone’s operating system. Most importantly, security updates help prevent hackers from exploiting vulnerabilities in your phone.

Manufacturers generally support high-end handsets longer than cheaper phones. I wouldn’t buy a phone released more than three years ago if it’s a high-end model, or two years ago if it’s a mid-range phone range or less expensive. We’ve found phones still for sale that have less than a year of guaranteed support remaining or are already no longer supported.

Use our telephone support calculator to know when we estimate each phone will lose security support.

3. Buy the first offer I see

If you’re buying your phone outright (and not through a contract), it can be tempting to go for the first discount you see at your favorite retailer. But I’d always shop around first, even if it’s just a quick Google search for the handset.

Many phone deals come with freebies sold as “bundles” instead of big overall discounts. Examples we’ve seen include a free pair of Samsung headphones with purchase or access to a free Apple TV subscription for a few months. It’s worth checking the phone manufacturer’s deals as well as those from retailers and mobile carriers – Google And Samsung In particular, regularly get discounts and gifts built into a new purchase, so check what’s on offer before you buy.

Contracts usually come with add-ons like free streaming services or even free gifts, but these are usually built into the contract repayment in some way, so use our calculator above to check this before purchasing.

Are you looking for a new handset? We’ve rounded up our picks from the latest Android and Sim Phone Deals And iPhone deals.

4. Buy an ultra-premium phone

Most major phone manufacturers reserve the crème de la crème of the latest features and upgrades for an ultra-premium device at the top of their flagship lineup. It could be a sharper screen, a faster processor, or more advanced cameras.

However, most people might not even notice these upgrades, especially compared to cheaper phones in this flagship line. For example, often one of the biggest upgrades is an additional telephoto lens to give you the sharpest images when you zoom in a lot. But the frequency with which you plan to take enlarged photos probably won’t justify the extra money you’ll pay for a high-end phone. So consider opting for a cheaper option.

We’ve also noticed that mid-range and even entry-level phones perform better and better in our tests. They may not have built-in AI capabilities, but the core features (think screen quality, battery life, and speed for everyday use) are good for a a number of them. If I was looking to balance value with performance in a phone, I would buy outside of the highly advertised flagship ranges.

Brands are betting big on AI in new smartphones – find out what happened when we test Samsung AI in our laboratories.

5. I can’t take care of my phone

If you don’t take care of your phone, its performance may decline faster than it should. Here are our top tips for keeping your phone in its best condition and protecting your data should the worst happen.

Secure your phone as soon as you receive it

If you lose your phone or it’s stolen, your best chance of finding it and securing your data will be determined by the steps you took before it disappeared.

As soon as you have your phone, configure Find my device on an Android phone or Find my iPhone on an Apple iPhone so you can track and control it remotely. Manufacturers are improving these features, too: on some Android phones, Google’s AI can automatically lock the screen if it detects it’s been stolen, and Apple won’t allow major changes to be made to your iPhone when it is located far from your common locations without additional authentication. .

• Read our advice in what to do if your phone is stolen for more important tips.

Clean it often

We take our phones everywhere and they can pick up a lot of bad bacteria along the way. I use a 70% isopropyl alcohol wipe to disinfect my phone, but you can also use mild soap and water with a damp microfiber cloth (we recommend a lint-free cloth).

• This must be done carefully – our guide on how to clean your phone without damaging it explains why.

Keep things tidy

A common complaint from Which? members are running out of storage or battery life isn’t as good as it used to be. Offloading unused apps on iPhone – deleting an app without deleting its data – can help alleviate these problems. It’s also a good idea to simply delete apps that you never use. Closing apps to prevent them from running in the background can help, but a good measure in general is to restart a phone every now and then – once a week is good, to clear things up.

Keep it updated

You may find the reminders that appear on your phone’s screen to update its software annoying, but it’s important to take the time to update it so that security patches are installed. Without this, vulnerabilities can appear in your phone’s software and be exploited.

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