Touchscreens on a BlackBerry device are easy to use after a short learning curve. The touchscreen allows you to bypass the navigational key and keyboard in favor of using the on-screen keyboard and touchscreen navigation. Now and again, you may find that your normally responsive touchscreen stops responding to taps and swipes. As with other electronic devices, you may need to reset your BlackBerry to regain use of your touchscreen.
Press the "ALT," "DEL" and "CAP" keys on your BlackBerry's keyboard simultaneously. This performs a soft reset, which is similar to powering your BlackBerry off and then back on. If the screen is still not responsive when the BlackBerry reboots, you do have additional options.
Remove the back cover from your BlackBerry handset and remove the battery.
Press and hold the "Power" key for 10 seconds.
Replace the battery and allow the BlackBerry to power on. This performs a hard reset, which should reset the screen. If the screen is still not responsive, contact your provider's technical support department for assistance with replacing the device.