Include the country code (+1, +44) so it works abroad.
Optional. They can edit it before sending.
"iPhone + Android" writes ?&body=, which both iPhones and Android phones read. The standard form, ?body=, is cleaner but some older iPhones drop the message.
The Messages chat that opens, message typed in.
Text link (sms:)
sms:+15550100199?&body=JOIN%20to%20get%20my%20weekly%20drop%20list
Call link (tel:)
tel:+15550100199
Ready. Tap the links on your phone to test them.
Free SMS Link Generator by Hiyaly