Phone Dialing App for iPad Air 3

The only telephony software on your iPad is Facetime. You can use it to call other people with Apple devices.

There is also no included calculator. However, there are hundreds of calculator apps available in the App Store.

There is no iOS default calculator app for iPads and never has been. You will have to select a free or for fee calculator app from the App Store to use instead.

As for phone dialing, you will need a VOIP service. An iPad is not capable of even connecting to any cellular telephone voice network, so the only calls it can make are internet VOIP calls using something like the included FaceTime app, or Skype or some other third party VOIP app and service (Ooma works on iPads).

If you have an iphone you can pair the iPad to it to share the iPhone's cellular telephone capabilities - see Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch - Apple Support

First of all, iPad is not a cell phone, so the native phone app on iPhone would be of no value to an iPad. Even if you purchased a cellular iPad, it is for data only as iPad does not have a cellular radio like a cell phone.

Since you admit this is your first Apple device, you won't be able to make or receive phone calls on the iPad. If you owned an iPhone, you would be able to via Apple Continuity Services, but that won't help you if you don't have an iPhone. There are 3rd party apps you can use, such as Skype.

Apple just doesn't include a calculator app natively on iPad, but there are loads of Calculator apps, many which are free, you can download from the App Store.

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