I upgraded a 4th gen and it is worthwhile. Much faster, battery on my old is starting to lose runtime.
This new one feels lighter to me, but maybe its the case I had on the old one.
The charger with the 9th gen uses USB-C, which can transfer more power. Charging time seems to be about the same.
The camera can now follow you in Facetime similar to the Facebook portal. You can now move around and remain in frame.
Try it. There's a return window if you do not think its worthwhile.
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