TLDR: To install Thirdfort, update your device if needed. For iPhones, go to Settings, General, Software Update. For Android phones, go to Settings, Software Update to install the latest update.
Updating your device
To install Thirdfort, you may need to update your device if it's been a while since you've done this. If an update is needed, your phone will have a pending update, normally in your settings app.
Updating iPhones
To update an iPhone, please go to the Settings App and select General < Software Update. From here you can then install the latest update from Apple.
Updating Android Phones
To update an Android phone, please go to your Settings App and select System < Software Update. From here, you can then install the latest update from the manufacturer.