What are the difference between a segwit and legacy wallet I am installing a mobile wallet and it ask me what type of address I want to use, I want to try and use a segwit address but is there a risk that my coins will be lost if I try to transfer fund from an exchange if they dont support it, or if I want to transfer coins from my segwit address to a legacy one.
There are, broadly, three types of addresses in use at the moment:


P2PKH - Pay to public key hash addresses start with a 1, and should be accepted by essentially any service in the Bitcoin ecosystem
P2SH - Pay to script hash addresses are commonly used for multisig, but as of the segwit activation, they are also used for wrapped segwit addresses. These start with a 3. In the wrapped segwit version, you get the advantage of lower fees, while still being able to send to the address from nearly all services.
Bech32 addresses - Starting with a bc1, these are also known as native segwit addresses, and offer the greatest savings in fees. However, a sizable number of services do not support withdrawals to these addresses.


Generally, P2SH segwit addresses offer the best of both worlds at the moment.

When sending coins to a service, your choice of address does not matter. It only plays a role when receiving coins.