Twilio SMS Auth Integration

I need Twilio wired up to both the iOS and Android versions of my mobile app so users can verify their phone numbers and complete two-factor authentication with a one-time SMS code. My Twilio account is already active; what I am missing is the clean, production-ready implementation on each platform.

Here’s what I expect:

• A lightweight, well-commented integration of the latest Twilio SDK or REST API that sends and verifies OTPs for sign-up, login, and sensitive in-app actions.
• Solid error handling, automatic retries where appropriate, and clear user feedback states.
• A brief setup document or inline README so future developers can adjust credentials or tweak message templates without digging through the code.
• Demonstration that the flow works end to end on both iOS and Android builds (simulator or physical device video is fine).

Success for me is being able to flip the feature flag in production and have users move through SMS and two-factor verification seamlessly. If you have shipped similar Twilio integrations before, I’d love to see a quick reference or code snippet.