The UK’s main mobile providers (Vodafone, EE, 02 and Three) automatically block 18+ rated content through Active Choice network-level filtering system. However, when connected to Wi-Fi (at home or elsewhere) these filters won’t apply.
Parental control options for mobiles include:
Android (LG, Sony, Samsung, Huawei, HTC, Nokia, Motorola)
You can limit which apps, games and content can be downloaded and disable features such as location and camera. Read here for more detailed tips
There are on/off systems for features such as Facetime, in-app purchases and Safari. Read here for more detailed tips
Windows 10 Phone (Lumia)
The My Family option lets you restrict the games and apps that can be accessed. There’s also the Apps Corner option, which limits content if your child borrows your phone. Read more