Yes, you can use any charger that's designed to charge a phone or tablet and has, or connects to, a micro USB cord. As Rukbat said, if the charger puts out less current than the OEM charger, it will take longer to charge. If the charger you're using puts out more current than the OEM, it won't hurt anything because the phone and battery control the maximum charge rate.
All current phones and tablets are designed to work with 5 volt charging circuits, but if you want to use a charger and don't know it's provenance, you might want to be sure it outputs 5 volts. All USB chargers should do so, but it never hurts to be sure.