The iPhone is a phone, so you would surely have use of a shortcut to call with a single touch!
Plus you can complete with other shortcuts for home, work, friends, parents... Most of them are free!
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What makes it special?
With this dialer, save 2 phone numbers: the 1st one is not answering? start the app again, and call the 2nd one!
When the app is restarted after a short delay, youre given a choice for which number to call.
The configuration is intuitive at first launch. You can then use apps settings (in iPhones Settings) to reset the app and start the configuration over again, or change parameters directly.
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Remarks:
- You can download the app on any iOS device but... it requires iPhones phone function!
- Phone numbers can not contain special characters like *, and #.