Mobile Phones

This is one of the most important features, as it is the first thing you see at a glance, so it deserves special attention. Nowadays there are devices of various sizes, but the screen size of the most popular devices currently ranges between 6 and 7 inches. In any case, there are smaller and larger options to suit users' different preferences.

But beyond the screen, it is also important to look at the resolution, which ideally should be at least Full HD, Full HD+ or QHD+, if you want a sharp and detailed image. Do not overlook the refresh rate either, as it affects the smoothness of the display and the touch responsiveness of the device; a rate of at least 90Hz is preferable for a smoother, more responsive experience, whether you are gaming or browsing social media.

Another aspect to consider is the type of panel. Mid-range and budget phones use LCD panels, while high-end phones are characterised by AMOLED screens, very advanced panels in terms of brightness, contrast and energy efficiency. Finally, you should also consider aspects such as screen durability. In this respect, high-end phones are starting to fit Corning Gorilla Glass Victus, which offers greater resistance to scratches and drops, providing more durability and protection for the device against accidental knocks.

Camera quality is another of the most important aspects when buying SIM-free phones. Nowadays almost everyone uses their smartphone to take photos and record videos, whether with family, friends or a partner. Mid-range and high-end phones usually have multiple cameras, as these allow photos to be taken in different modes, such as wide-angle, macro or portrait with a bokeh effect.

That said, although most people only look at the number of megapixels, which allow a photo to be enlarged without losing quality, there are other factors just as important, if not more so. Aspects such as the quality of the image sensor or the aperture are fundamental for obtaining good photos and videos. So is the computational processing of the image through artificial intelligence, a feature that stands out in phones from brands such as Apple, Google or Huawei, capable of delivering excellent results in all kinds of scenarios.

The processor, RAM and storage capacity are the main factors responsible for a smartphone's performance. Nowadays 8-core processors have become standard, although for basic use a quad-core processor may still be enough in most cases. Qualcomm Snapdragon processors, Samsung's Exynos and Huawei's Kirin are leaders in the Android smartphone market, while Apple's A-series chips in iPhones stand out for their high power, according to various performance tests.

RAM is also one of the crucial aspects to consider before buying SIM-free phones. After all, a very powerful processor is no use if the RAM is not up to the job. Ideally you should have at least 6 GB for a smooth experience, especially if you use demanding apps or multitask, although people who make more basic use of their smartphone may get by with 3 GB.

Finally, when it comes to storage, phones nowadays offer more and more space, as part of it is taken up by the operating system itself. The 32/64 GB capacities that phones had a few years ago are now too limited in most cases, which is why most smartphones come as standard with a minimum of 128 GB, the space needed for the large number of photos, videos and apps that users keep on their devices today.

Whether a smartphone is mid-range or high-end, battery life has become a fundamental aspect, mainly due to today's connectivity demands. We all want our smartphone to keep us company throughout the day without needing frequent recharging.

My personal advice is to prioritise batteries with a capacity of at least 3500/4000 mAh, since thanks to the efficiency of key components such as the processor and screen, they provide long battery life. In any case, if you are going to use the device intensively, calling, watching videos or gaming, you should consider buying a smartphone with a larger battery.

Do not forget to consider key features such as fast charging technology too when choosing your new SIM-free phone. This charging system can make all the difference to how quickly you can recharge the device in an emergency or when you need to use it again quickly.

Finally, the operating system is another key aspect to consider before buying SIM-free phones. To begin with, there is no perfect operating system, as each has its pros and cons. The choice between them has more to do with personal preferences and use, and with how well it syncs with the other devices you own, as it makes integration and continuity between services and apps easier, improving the overall user experience.

iOS from Apple, Android from Google and HarmonyOS from Huawei are the main options available today. iOS, the operating system of iPhones, offers seamless integration with the rest of the Apple ecosystem (Mac or iPad) and optimises the phone's performance thanks to its comfortable, intuitive interface. On the other hand, it is not always compatible with some non-Apple devices such as smartwatches or other types of wearables.

Android, for its part, is a very popular operating system and offers great scope for customisation, which most brands use to add features or their own interface. Its main advantage, besides being compatible with most devices, is its price compared with iOS, as there are very affordable budget Android phones. Lastly, HarmonyOS, Huawei's operating system, is emerging as a promising alternative that allows smart devices to be integrated seamlessly into a connected and efficient ecosystem.