Need to check the state 'residency' requirements/restrictions.
Some states require a physical presence in-state in order to maintain state residency.
No state income tax is the least of issues.
DL's, vehicle registrations, insurance (vehicle & medical) require a 'physical' address that is recognized/accepted.
Some RV friendly states----FL, SD, TX.
They have mail forwarding services that provide a 'recognized' address and are easy to establish 'domicile'
BUT........with the Obamacare mandate medical insurance coverage can be an issue as some of the providers are not accepting a PMB (private mailbox) address (which is what you have with a mail forwarding service)