No filter is ever perfect though the default browsers that are available on mobile devices do not filter the websites that can seen by the user.
Safari does offer an Adult Content filter as part of its parental control features.
SPIN Safe Browser goes further by enforcing strict safe search via Google, Bing and Yahoo and blocks many grey areas that Safari does not.
Recommendations - Making SPIN your default browser:
For Android home users: you can use our companion apps, Boomerang Parental Control or Manage SPIN on Android to block all web browsers except for SPIN Safe Browser.
For iOS home users: leverage the built-in restrictions to block Safari (it hides it). Then SPIN Web Browser can be used as your main browser. Please note iOS doesn't allow the user to change it's default browser (so when you open links, they may not do anything unless you copy/paste them into SPIN's address bar) and iOS doesn't prevent you from accessing other third party web browsers that do not filter the web.
For Schools with iOS devices: leverage the power of your MDM to control various aspects of SPIN for iOS. Contact us for additional information at SPINMDM@nationaledtech.com.