On the Wi-Fi + 4G version, you can use either Wi-Fi or 4G LTE, depending on what’s available. The system features are the same in both modes. The main differences are connectivity and battery usage. Battery life may vary by network mode. In general, 4G mode can last longer, up to 10 hours of continuous use, while Wi-Fi mode is up to 5 hours. Your actual results may vary depending on signal strength and usage. If you plan to use Wi-Fi mode, we recommend using your phone’s personal hotspot for the best experience, as it is often more stable than crowded public Wi-Fi. If you plan to use 4G mode, 7-Cal is designed to use a nano IoT SIM Card. Please insert your own IoT SIM card (we provide a step-by-step guide on the manual page). Note: If you are comparing product versions, the Wi-Fi version supports Wi-Fi only, while the Wi-Fi + 4G version supports both Wi-Fi and 4G. For full details, please refer to our Tech Specs page.

7-Cal WiFi+4G Version is designed for a 4G IoT SIM card (CAT-1). Some consumer phone SIM cards restrict IoT devices, which will cause connection failures even if 4G LTE is supported. We recommend using an IoT SIM card, such as Hologram (Global), which is designed for LTE CAT-1 / CAT-4 devices with the highest compatibility. You can also search for your own local IoT SIM Card providers. Based on our testing, some phone SIM cards may also work directly. For example: Israel: Partner Singapore: SIMBA Spain: DIGI UAE: Etisalat (e&)/du UK: FlexiFone/O2 You can insert your own SIM card after receiving the device. A step-by-step setup guide is provided in the manual. You can follow the 4G connection guide to ensure a smooth 4G experience on your 7-Cal device.

If you experience issues connecting to 4G on your 7-Cal device, please follow the steps below to troubleshoot. 1. Use a Compatible IoT SIM CardThe 7-Cal WiFi+4G version is designed to work with IoT SIM cards. Please make sure your SIM card:is an IoT SIM cardsupports 4G LTE (not 2G/3G/5G only) & LTE CAT-1Many consumer SIM cards restrict usage in IoT devices, which may prevent device from connecting to the 4G. If your SIM card is not for IoT use, the connection may fail.2. Activate the SIM Card and Remove PIN LockSome IoT SIM cards must be activated first using a phone before they can be used in IoT devices. Please activate the SIM card if required by the carrier, and remove any PIN or PUK lock from the SIM card through the phone settings.3. Configure the APN Settings & Data roamingPlease set the APN manually. Go to https://apn.how/ and select your country and carrier to find the correct APN.  Please insert the SIM card into a phone, set the correct APN, enable data roaming, and confirm that the phone can connect to the network. Then reinsert the SIM card into the 7-Cal and enter APN under Setting → Internet → 4G Settings → Custom APN.  Then try connect the 4G. Recommended SIM Card Option: Hologram (Global) • Provides IoT SIM cards• Works in many countries and regions• Designed for LTE CAT-1 / CAT-4 / IoT devicesYou may use Hologram or any other local IoT SIM card provider in your region, as long as the SIM supports 4G LTE (LTE CAT-1) connectivity for IoT devices. Based on our testing, some phone SIM cards may also work directly. For example:Israel: Partner Singapore: SIMBASpain: DIGIUAE: Etisalat (e&) / du UK: FlexiFone/ O2

You can view both the APN and IMEI directly in the 4G Settings on your 7-Cal calculator. These details are useful when configuring a SIM card or contacting your carrier for activation. For step-by-step instructions and additional details, please refer to the user manual.