Success confirmed on my 17 SR5 Premium as below:
Panlong OBD2 scanner model PL-W03
https://www.amazon.com/gp/product/B019IGO9DA/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
Carista app from Apple on iPhone running iOS 10.2.1
- Plug scanner into OBD port located under the dash next to parking brake
- Turn ignition to 'on'
- Enable WiFi on the phone and connect to the scanner
- Open Carista on phone, click on Customize and you will be prompted to connect to whichever device you are using and then it will scan for the available customizations
When you first start, select just one setting to change, save it and then you will be prompted to disconnect from the OBD2 device in order to connect to the internet. This should then take you to your purchase options. Select the trial period and as long as you cancel the subscription in 6 days (apparently you need to cancel a day before the trial ends) you are good to go.
Once you get verification of the trial being enabled, close Carista and turn off WiFi. Turn WiFi back on and then reconnect via Carista. Select your desired customizations and you are all set. From start to finish it took me just under 15 minutes.
I just need to remember to cancel the subscription by the 18th.
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