I need to check if the balance on my wallet is still there without log in to it.
Can I check an used address on which I deposited earlyer via explorer? Or is it possible that this address shows balance even when somebody send all IOTA via an later generated address?
On a tangle explorer, you can check the address you used to receive iota. The balance will still be on the address, assuming you have not sent iota from it.
Yeah you can always check the current balance of an address through an explorer.
In a normal usage scenario, the last deterministically generated address will contain the whole balance belonging to a given seed (the wallet will send the remaining balance of an address to the next address on every tx, so you don't reuse addresses).
You can however have balances on multiple addresses belonging to a seed, in this case you will not see the entire balance you own (via a seed), but only the balance on the specific address you're viewing.
