Apple Store trade in amounts are usually better as well. Plus if you have the Apple credit card, you get 3% cash back and 12 months free financing.

The trade in value for my iPhone 13 PM was $830 at T-mobile and Apple was giving less...

Yes, that is if you are on one of the new 5G plans. JOD or legacy plans do not get that promotional rate, but we also pay less for our monthly plans.

Additionally the promotional trade in on the 5G plans give you two forms of credit:

1. Up-front credit - this is the “real” trade in value which is usually lower than Apple.
2. Promotional credit - this is the remainder of the promotional trade in amount that is paid out in 24 monthly credits. In the latest terms for this promotion, you have to keep your line for 24 months. If you pay off your balance early then you lose any remaining promotional credits.

Apparently it was only in the good ole days when T-Mobile thought it was important to make their customers actually feel like there were doing business with the un-carrier.  Guess I will have to start hoping from company to company every time I want an upgrade instead of being a customer who is loyal because the company makes me feel well cared for! 

I've been with Tmobile for 20+ years and I use Pixel phones and I've been buying directly from Google for my last 3 phones. Better pricing, trade ins are easy and you get what they quote.

Also their financing is better imoh.

Can you bring a phone that you didn’t buy from TMobine and keep your plan? I’m worried if I do that I’ll have to change plans or numbers

Yes, so long as it’s network compatible and most are these days. 

The only minor glitch is your phone won't show correctly on your account. I had my Pixels listed as an iPhone, Samsung and unlocked Android and seems to changes every time I go to MyTmobile account.

This is the offer that plans that are not 5G Next or Plus get:

Apple trade in for my iPhone 14 Pro was $100 more.

Yeah, I’m on a legacy plan and it’s clear they no longer value long time customers so, I’m looking for my next carrier, someone who might be more appreciative of customer loyalty. 

Can I switch plans to one of the Go5g plan and then qualify for the better discount?

Sure you can but it’s not necessarily a better deal.  In my case for example, it’s actually cheaper monthly to keep the current plan I have and purchase a phone than it is for me to change to the new plans and use the larger discount.