I am currently staying at an apartment which is rented by my german roommate. I have a separate sublet agreement with him regarding my contract.

This month end I will be moving to a new place and my roommate will be going back to germany. Apart from this, I am also planning to move to singapore by mid march.

I am very concerned about my apartment deposit as both me and him have plans to move out of switzerland soon. In case of any problems, it is very difficult and expensive for me to come back to switzerland and pursue legal action.

What should I do? What are my rights in case of any problem?

If you sublet, it is the person you signed paperwork with that has to return your deposit. He then has to turn around and settle things with the landlord. As you are suspecting, this can get pretty messy if someone refuses to pay, or if your housemate thinks he is only going to return 'your' deposit once the whole deal is settled with the landlord...

Did you pay a deposit to your housemate? Was it lodged as an 'official' deposit or was it just handed over as cash into his pocket ?

I paid to my housemate. It was transferred to his account directly. In the contract, it is mentioned that i have given the deposit.

simply have him deposit it back.....if you are on good terms with him. If you can wait have him transfer it after the lease is over. you can transfer from everywhere in the world....