I have just recently cracked my galaxy s7 edge and i have insurance but i was wondering if ugrading early to a galaxy s8 and the early upgrade fee is cheaper or just as expensive as replaceing my phone with my insurance
Unfortunately, the only real way to know is to get in touch with Sprint and compare the exact numbers for each scenario.
But keep in mind, there's more than just costs to consider.
There's also a middle-ground option... you could see what used phones are available for a similar price to your insurance plan. Depending on prices, you might find an option you like and get a better warranty in the process.
Of course, that depends on who you buy your phone from.
Once you've bought the used phone, you could ditch your carrier insurance and use someone like SquareTrade for a small one-time fee and pocket the savings toward your next upgrade.
Whichever route you choose, we hope you find something that keeps you connected :)