Using a 4G SIM in an Apple iPhone 4

If you have an Apple iPhone 4 and you want to use a 4G SIM card, follow these detailed steps. Though your device is not 4G compatible, you can still use a 4G SIM card, but it will function at 3G or 2G speeds owing to the hardware limitations of the iPhone 4.

Check Compatibility

It is important to check the compatibility of your iPhone 4 with a 4G SIM card. Unfortunately, the iPhone 4 only supports 3G HSPA and 2G GSM and does not have the necessary hardware and software to support 4G speeds. However, you can still use a 4G SIM card in your device, but the device will connect to 3G or 2G networks, not 4G.

Obtain a 4G SIM Card

Once you are aware that your device can only use 3G or 2G speeds, make sure you obtain a SIM card from your carrier that is activated for 4G service. While this SIM card is activated for 4G, it will function at 3G speeds or lower depending on the capabilities of your device. Ensure that the plan is compatible with older devices as some carriers may limit functionality on older models.

Insert the 4G SIM Card

Power off your iPhone 4.

Use a SIM eject tool or a paperclip to open the SIM tray located on the right side of the phone.

Insert the new 4G SIM card into the tray, making sure it is oriented correctly. Note that the card should have the chip facing up towards the inside of the iPhone 4.

Push the tray back into the phone until it clicks into place.

Power On the Device

Turn on your iPhone 4. It should recognize the new 4G SIM card and prompt you to set up any required network settings.

Configure Settings

If prompted, follow any instructions to set up your network settings. You may need to enter APN (Access Point Name) settings for data services. These can be obtained from your carrier and should allow you to access mobile data and other internet-based services.

Test Connectivity

After completing the setup, check if you can make calls, send texts, and access mobile data. Keep in mind that while the device can function with a 4G SIM card, the speeds will be significantly lower due to the 4G SIM card functioning at 3G or 2G speeds. The theoretical maximum data speed for 3G HSPA is 14.4 Mbps, which is lower than 4G speeds.

Remember, the iPhone 4 is not 4G ready. It lacks the necessary hardware and software support chips, OFDMA modulation code, and firmware for 4G operation. As such, it cannot be used in 4G LTE mode on any network.