How we collect opt-in and store data in my app

I am a solo developer and building an app that enables businesses to send messages to their customers. My customers will collect opt-in consent from their end-users and store that consent within my app.

– Opt-In Method:
My customers will collect explicit consent from their end-users before sending any messages. The consent can be collected verbally, or their check-in app like Square, Fast Boy, Clever. But after they asked their end-users, they will type the name and phone, my app will store their opt-in again on my app. All collected opt-in can be exported any time to be proof from Twilio or other party to collect the compliance.

– Verbal Consent Script :
“Are you satisfied with your nails today? If you are, we’d love to send you a quick link for feedback.”

– How Consent is Stored:
My app provides a feature for my customers to record and store the following for each end-user:
Name
Phone number
Date and time of consent
Method of consent (verbal)
The consent script used

– Each record sample :
Phone: +1XXXXXXXXXX
Consent Type: SMS Opt-in Collected via: Mobile App (iOS/Android)
Timestamp: 2026-04-21 14:32:10 UTC
Method of consent : verbal – “Are you satisfied with your nails today? If you are, we’d love to send you a quick link for feedback.”

– Opt-Out Instructions:
All messages sent through my app will include: “Reply STOP to unsubscribe.”

– Sample Message:
“Hi [FirstName] ! Thanks so much for coming in today . If you have a moment, we’d really appreciate your review: [ReviewLink] .Reply STOP to opt out”

– How many times sms to send to customer :
Only 1 time sms to each customer , never again. 5-20 end-users customers a day.