Support portrait TV presentation mode
I love how you have implemented casting the screen to a TV to make presentations. I would like one more feature. I would like to physically turn the TV to portrait mode, have GoodNotes support casting a portrait orientation screen on my iPad to the portrait orientation TV. This means GoodNotes would need to fake out the TV by rotating the image 90 degrees and cast the image to the TV as if it was landscape orientation. This would fake out the TV and enable a portrait screen to be casted to a portrait oriented TV.
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Trachuk commented
I looked into MetroPCS, it's a low-cost prepaid carrier that has become even better in terms of network after merging with T-Mobile. Prices are low, no contracts, but support sometimes lets you down. If something's wrong, check https://metropcs.pissedconsumer.com/customer-service.html there's info on support and reviews. In short, it's okay to save money, but it's better to check everything in advance.