In case you would like to have remote access to your system, there several ways to do this.
IoT-Bridge by Pekaway
Our IoT-Bridge is built on top of the LILYGO TTGO T-Call SIM 800 board. It connects to the VanPi system via wifi and bridges it to the gsm/edge network. It requests needed data via the built in HTTP-API and transmitts it to a server hosted by us (located in Germany), which then redirects it to your mobile device (Pekaway app needed, will be released soon!).
The C++ code used by the bridge is closed source for now (you may be able to use it with your own simcard and custom setup in the futere. To use it with a custom built setup you will need an available MQTT-Broker (e.g. installed on a VPS).)
We will offer a ready to use version of the bridge in our shop. Including the hardware and an IoT-SimCard. You can find the Pekaway apps for Android and iOS in the appstores as soon as we will release the production version. These mobile apps are not open source!
Remote-Red is a nice tool to tunnel your dashboard directly to your smartphone. This app costs about 10$ per year, including push notifactions. It is easy to setup and use.
Of course you can also use an VPN to connect your system. Quite often there may be problems with shared ip-adresses on LTE connections, which makes it not that easy to connect your VPN. Please also keep in mind to secure your system accordingly when using VPN.