Again, you'll need someone else to set the passcodes for the parental controls so you can't undo them. They should also do regular checks to make sure you haven't reset your gadget to factory settings.
If you can't tell, there are ways to bypass any blocking software, especially if you set it up yourself. That's why blocking and filtering software is only part of the equation; you also need accountability.
Look at an accountability program like x3Watch. It watches your browsing and sends emails to a trusted friend if you visit a questionable site. The developer, XXXchurch, is also a great resource for understanding and fighting this kind of addiction.
Other programs like Covenant Eyes or Ever Accountable offer more advanced features and mobile support. They do require a subscription.