Sure, it’s handy that your smartphone can remember and fill in usernames and passwords for your various web accounts. But it also means anyone else with access to your handset can log in to your most sensitive accounts, too.

Indeed, the more often you tap “yes” when your iPhone or Android phone asks “Would you like to save this password?”, the more saved passwords you have sitting in your pocket—and that could lead to big trouble if your precious smartphone ever lands in the wrong hands.

A good rule of thumb is to select “Never for this site” or “Not now” when your phone offers to save passwords for your most important accounts, such as your online banking site.

But what if you’ve already saved passwords for more sites than you can count?

In that case, you might consider starting fresh by wiping all the web passwords from your iPhone or Android phone’s memory.

For Android phones:

• Open the Browser application, tap the Menu button, select Settings, then tap “Privacy & security.”
• Scroll down to the Passwords section and tap “Clear passwords.” You’ll get one last chance to change your mind; if you’re ready to go ahead, tap the “OK” button.
• If you want your phone to stop asking to save web passwords, clear the check from the “Remember passwords” checkbox.

For iPhone:

• Tap Settings from the home screen, then tap Safari.
• Next, tap AutoFill, then tap the “Clear All” button under the “Names & Passwords” setting.
• To keep your iPhone from saving any more passwords, flip the “Names & Passwords” switch to “Off.”

Click here for more Android tips, or click here for how-tos about the iPhone.