Can i get carpal tunal from too much texting, playing games, and web browsing on smartphone? what can i do to prevent it ? what symtoms would i have ?

Yes: Cts can cause numbness, tingling in thumb, index finger, middle finger, & half of the ring finger (may feel like all fingers & palm) may give you the urge to "shake" the hand out. Also: hand pain, weakness. All symptoms can feel like they are radiating into arms as well; symptoms may start at night & wake you up. Avoid overuse. We often use splints at night to avoid pinching nerve w/ bent wrists.