Microsoft Lumia 640 XL LTE Dual Sim Specifications, Tests and Review

The Microsoft Lumia 640 XL LTE Dual Sim has a height of 157.9 mm, a width of 81.5 mm and a thickness of 9 mm. The weight of the phone is 171 g.

The screen size reaches 5.7" inches. With a large display, phone offers a great experience for watching videos, playing games and reading. The best phones today are 6.5'' or more. They have the advantage of a large display area that allows you to see more content than with conventional display sizes. LCD displays are currently taking a back seat. This is mainly due to higher power consumption. In addition, they have the disadvantage of lower colour contrast, which can be reflected e.g. in the resulting photos. On the other hand, phones with LCD displays are in general cheaper than those with OLED technology.

Display Resolution of Microsoft Lumia 640 XL LTE Dual Sim is 1280 x 720 pixels. A higher display resolution is a prerequisite for a sharper image. The standard for mid-range phones today is a Full HD resolution of 1920 × 1080 px. Cheaper phones, which usually have a smaller diagonal, have an HD resolution of 1280 × 720 px. Smaller resolutions can only be found in older models. Best phones, on the other hand, have a 4K resolution of 3840 x 2160 px. Display´s pixel density is 259 ppi and represents another significant factor affecting image sharpness besides resolution. The higher the value, the sharper the image. Average value is currently about 350-400 ppi, which guarantees a fine and sufficiently sharp image. Finest modern phone displays reach 450 ppi and above.

Microsoft Lumia 640 XL LTE Dual Sim is equipped with Qualcomm Snapdragon 400. The number of processor cores is 4. It is a number of cores that plays an important role in evaluating the performance of phone as it is responsible for computing operations. Smartphones already commonly have a core count of around 4 to 8. Multi-core processors can perform better and reduce the processing time of a request to a minimum, which is reflected in the responsiveness of the phone, e.g. in the speed of opening applications. The processor frequency indicates how many instructions phone can process in 1 second. The higher the frequency, the better the performance. Standard processor frequency range today is between 1.8 GHz and 2.8 GHz. Microsoft Lumia 640 XL LTE Dual Sim reaches the frequency of 1.2 GHz.

The phone´s internal memory capacity is 8 GB. The size of the internal storage determines e.g., how many photos, songs, movies, or applications you can store on your phone. This memory capacity is ideal for those who have a few basic apps and a few dozen photos on their phone. If you don't expect to use your phone to play games or need to store high-resolution photos, this size should be sufficient. There is almost no probability you're likely to see this low capacity on new smartphones. The standard memory today is around 64 and 128 GB. The best phones have internal memory of 256 GB or more. Luckily, most smartphone manufacturers nowadays offer models with different memory sizes to suit every user.

An additional option to increase the storage capacity of this model is to insert a memory card.

RAM memory of the Microsoft Lumia 640 XL LTE Dual Sim is 1 GB. Most powerful phones currently have an operating memory of 12 GB or more, which is especially useful for demanding users such as gaming enthusiasts. Normally, phones nowadays have 6 to 8 GB of RAM, which means that the phone can easily handle normal operation and more demanding applications. Operating memory of less than 4 GB is found in lower-end phones or older models, and they are suitable for low-end users who don't use demanding applications and have the phone more for basic use.

The rear camera of the Microsoft Lumia 640 XL LTE Dual Sim has only one lens. Single lens is more typical for older phones or lower-end phones with lower quality cameras. The rear cameras of modern phones nowadays are usually equipped with two, three and sometimes even five rear camera lenses. The resolution of the main lens is 13 Megapixel. Higher resolution does not necessarily mean super high quality photos. Furthermore, it depends on the pixel size but also on other important factors. The aperture of main lens reaches F/2.0 value. The best phones have a lens with an aperture of up to F/1.5, where more light can pass through sensor and photos will be of a high quality even in low light conditions. However, lenses with apertures around F/1.8 to F/2.2 are the most common. The lower the number after the slash, the better the photo quality.

Digital zoom in this case offers zooming up to 4x. Of course, the higher the lens value, the more distant object can be zoomed in. Nonetheless, the disadvantage of digital zoom is that the quality and sharpness of photo deteriorates when using it.

Front camera
The front camera of phone Microsoft Lumia 640 XL LTE Dual Sim has one lens. This number of lenses is standard on most smartphones nowadays. The resolution of front lens reaches 5 Megapixel. Again, it should be noted that resolution is only one of several other significant factors that affect resulting quality of a photo.

The battery size of Microsoft Lumia 640 XL LTE Dual Sim is 3000 mAh. Nevertheless, battery capacity is not the only factor that affects the phone's battery life. For example - the size of the display, the performance of the processor, the use of data functions and, of course, the intensity of use of phone in general all have a significant impact on battery life. Standard for most smartphones today is a battery capacity of around 4500 to 5000 mAH. Phones with this battery size usually guarantee a phone life of at least 1 day. Older or cheaper smartphone models can then reach battery capacities typically around 2500 mAH and below. With this capacity, you may find that if you use your phone heavily, you may need to recharge your phone during the day.

Standby time is 888 hours and it expresses the maximum time your phone can last on a single charge when you are not actively using it. Talk time, or we can say battery life when making calls, then indicates amount of time your phone will last from a full charge if you are constantly on a call. Microsoft Lumia 640 XL LTE Dual Sim is provided with a talk time about 1800 minutes.

Microsoft Lumia 640 XL LTE Dual Sim supports 4G. 5G connectivity, which is slowly replacing standard 4G connectivity, is still more the preserve of the latest phones. The operating system in this case is Windows Phone OS 8.1 with Lumia Denim update (upgradable to Windows 10).

Fans of modern technology will appreciate NFC function, which allows, among other things, contactless mobile phone payments, but also finds other uses in connectivity, such as unlocking the door or loading the menu in restaurant using the NFC tag. Basic connectivity standards also include Bluetooth 4.0, making it easy to communicate wirelessly with other devices such as headphones, tablets, speakers and smartwatches.