1. iPhone: Focus auto-reply (free, limited)
iPhones can auto-reply while a Focus mode such as Driving is on. It's built in and free, but it was designed for personal use. According to Quo's guide to text autoresponders, the auto-reply only goes to people in your contacts, or people you've messaged recently, so a brand-new customer calling from an unknown number may never get it. It also sends one fixed message and can't ask follow-up questions.
2. Android: third-party apps
Android phones don't include a built-in "text back after a missed call" setting for every caller, so owners usually install a third-party auto-reply app. These can work for a single phone, but they run on that phone: if it's off, out of battery or out of signal, nothing is sent. Most send one fixed message rather than a conversation.
3. Business phone systems and missed call text back services
Some business phone services include an instant text reply. For example, Grasshopper offers Instant Response, which texts callers you miss. Dedicated missed call text back services go further: they keep the conversation going by asking questions and send the owner a summary.
That's what Oplari AI does. Unanswered calls to your existing number are forwarded, the caller gets a text in seconds, and they're asked your questions one at a time: the job, whether it's urgent, their name, address and best callback time, and a photo. You get one summary text. See how it works or try the interactive demo.
| Option | Texts new callers? | Asks questions? | Works if your phone is off? |
|---|---|---|---|
| iPhone Focus auto-reply | Often not (contacts or recent only) | No | No |
| Android auto-reply app | Depends on the app | Usually no | No |
| Missed call text back service | Yes | Yes | Yes |
Phone features change. Check your own phone's settings and the app's documentation.
The rules in Canada
Texts to people who called you are generally treated as replies to an inquiry, but you should still follow Canada's anti-spam law (CASL). The CRTC's CASL FAQ and guidance explain that commercial messages need to identify the sender and include a way to unsubscribe, and that unsubscribe requests must be honoured within 10 business days. For text messages, replying STOP is a common unsubscribe method.
In practice: say who you are in the first text, include "Reply STOP to opt out", stop immediately when someone does, and don't add people who called you to marketing lists without consent. Oplari AI's first message names your business and includes the STOP line, and STOP ends the conversation automatically. This isn't legal advice; check the CRTC pages for your situation.
Which should you use?
If you rarely miss calls and mostly hear from people you know, a phone setting may be enough. If new customers call your business line and you're often on a job, a missed call text back service that asks the right questions will tell you far more. Compare pricing: $349 one-time or $69/month, in CAD.