is the Alexa app free?

Yes, it is free for Android, iOS, Windows & Mac.
is the Alexa app on iPhone?

yes, it is available on iPhone/iPad.
is the Alexa app free to download?

yes, it is free to download
is Alexa an app or a device?

Both are available if you want. You can install the Alexa App on your Phone or you can directly purchase Alexa devices from Amazon.
can the Alexa app be shared?

I think you don't need to share it because it is available for free to everyone.
can the Alexa app be downloaded to the computer?

Yes, it can be downloaded. Follow this article for more information.
can the Alexa app be on two phones?

yes, it can be used on multiple devices.
is amazon Alexa have Bluetooth?

Yes, it has Bluetooth. You can use it as an external Bluetooth speaker.
can amazon alexa call 911?

yes, it can but it has to be available in your region.
can I use the alexa app in my car?

Yes if you have Android Car Stereo you can install it.