Understand the technology behind your UK mobile phone

An eSIM (embedded SIM) is a SIM chip built directly into your phone, activated by scanning a QR code your network emails you. There is no physical card to insert. Once activated, it works identically to a standard SIM: calls, texts and data over the same network. Most modern iPhones (XS and later), Samsung Galaxy S and Z series, and Google Pixel phones include eSIM support. All major UK networks support it as of 2026. Full setup walkthrough in our eSIM guide.

In UK cities on EE or Vodafone, real-world 5G download speeds typically land between 150 and 400 Mbps during the day, with peaks above 600 Mbps in good signal conditions. Latency drops to 10-20 ms, which is noticeably better than 4G for gaming and video calls. Outside city centres and in rural areas, 4G coverage still matters more than 5G access. Our 5G guide covers the operator-by-operator rollout map.

The hardware is free: dual-SIM capability is built into the phone. You pay for two separate plans. A typical setup is one SIM-only contract (10-20 GB data) for personal use at around £10-15 a month, and a second plan from your employer for work calls. Some travellers use a UK contract SIM plus a local data-only eSIM abroad to avoid roaming charges. See our dual-SIM phones guide for the best handset options.

Yes, from a reputable seller. UK-sold refurbished phones must carry a minimum 12-month warranty under the Consumer Rights Act. Grade A units are cosmetically near-new and functionally identical to a new handset; Grade B shows light scratches; Grade C has visible wear but works correctly. Avoid ungraded or "tested and working" listings without a warranty. Sellers like Back Market, Music Magpie and the manufacturer certified programmes (Apple Refurbished, Samsung Certified Re-Newed) are reliable. Full breakdown in our refurbished phones guide.

Not in the near future. Ofcom has confirmed there are no plans to retire 4G before 2030 at the earliest, and realistically 4G will coexist with 5G for many years after that. The 3G switch-off was completed by all major UK networks in 2024, but 4G is far more widely embedded and will remain the fallback network in rural areas and indoors for a long time. You do not need a 5G handset today unless the speed upgrade is specifically valuable to you.

Yes, on most modern dual-SIM phones. An iPhone 15 or later, for example, supports two active eSIMs simultaneously (no physical SIM slot at all on US models, while UK models keep one nano-SIM slot). Samsung Galaxy and Pixel phones typically offer one physical SIM slot plus one eSIM. Both lines are active for calls and texts; you choose which SIM routes data by default. Detail and compatible model list in our eSIM guide.

Sweatcoin is a step-tracking app that converts your daily steps into a proprietary digital token called Sweatcoin (SWC). The exchange rate is roughly 1,000 steps to 0.95 SWC. Tokens can be redeemed in the in-app marketplace for products, charity donations and, since 2022, exchanged for SWEAT cryptocurrency on the Near blockchain. The app is free, runs in the background and does not drain battery significantly on modern handsets. Whether the reward rate is worth it depends on how actively you use the marketplace. Full detail in our Sweatcoin guide.

EE leads for geographic 5G coverage, reaching the most UK postcodes including suburban and smaller towns, thanks to its early rollout start and BT Group infrastructure investment. Vodafone covers the most major cities with strong indoor penetration. O2 and Three have strong city-centre presence but thinner suburban reach. The honest answer depends on your home postcode: check each network’s coverage map with your specific address before committing to a 24-month contract. Our EE network page and the networks comparison have current rollout data.