The HTC One smartphone comes in two versions. The device, designed for one SIM-card, does not have a removable cover. And the variant with two SIM cards (HTC One Dual SIM) has one, but no NFC function.
Instructions
Step 1
To open the cover of HTC One, disconnect all peripheral devices (USB Host adapter, computer, charger, headphones, etc.) from your smartphone. Unlock the screen, and then press and hold the power button for a long time. A menu will appear. Select the item "Turn off the phone" or similar (depending on the firmware version). Do not confuse it with the "Reboot" item. A new menu will appear. In it, select "Yes", "Disable" or similar. Wait until the device turns off completely.
Step 2
Turn the phone with the screen facing you, with the USB connector down and the headphone jack and power button up. On the left side wall, you will find a lever. Pull it towards the top wall where the headphone jack and power button are located. The back cover will unlock and you can remove it.
Step 3
The smartphone's battery is non-removable, so you won't find it under the cover. Therefore, make sure that the power button is not accidentally pressed when the cover is removed, since it is undesirable to change the SIM-card and memory card when it is switched on. But in the compartment there will be two slots for SIM-cards, as well as one slot for a Micro SD memory card. The single SIM variant of HTC One does not have a cover and does not support a memory card.
Step 4
When installing SIM-cards, choose correctly which of them to install in which slot. One of them (the top one) allows you to use 3G, and the second does not. On the card that you are going to use to access the Internet, an unlimited tariff must be connected, and it itself must be in the home region. Micro SD memory card can be up to 64 gigabytes in size.
Step 5
After inserting the SIM cards and memory card, replace the cover. Turn on your smartphone by long pressing the power button. Wait for the Android operating system to load. Reconnect peripheral devices as needed. Continue using your phone.
