What to do with your mobile phone and connection in India?

Mobile Connection
I have a connection with Vodafone, Mumbai. So the procedure/rates I am mentioning are of the same. I am pretty sure it should be similar in most other services. Now, you are going to be staying at Singapore for long term. For those who are on contract and know the term that they will stay here can also note the suggestions. I will mention 3 solutions.

Solution I
Put your connection on International Roaming(IR)... Yes, I have done this:- Well yeah sounds absurd, but read through this.

Converting to pre-paid
Convert your connection to pre-paid if you have a post-paid connection and if you want to keep you number. Else you can buy a new connection. There is no difference. Now, if you have to activate IR with post-paid number, you need to pay heavy deposits in range of 5000 to 10,000 INR. This is obvious as it is possible that you might run away without paying the bills. Also the IR charge is 149/month in post-paid compared to 99/month in pre-paid.

Procedure
For converting your number, first clear the unbilled usage then you will need to submit photo-id and residence proof again. There are no transfer charges. You need to pay 99 INR for new sim (Post-paid sim cards cant be used for pre-paid connections) and make a minimum recharge for activation (I chose 10 INR). This 10 INR balance is with validity of 24 hours. Now even if you start with 200 INR, the validity would be 24 hours. So now you need to buy another recharge depending on you usage. First I purchased a recharge of 199 INR with lifetime validity. You get talktime of about 10-25 INR in this. Then I purchased a recharge for 200 INR (now the validity of this is lifelong). Your conversion is complete here. This whole process takes about 1 working day. Once your number is on pre-paid connection, your previous simcard will not work. Now you can also put a claim for your initial deposits with the post-paid account.
Catch: Even though the number has lifelon validity, you need to recharge atleast 200 INR in 6 months, failing to do which your number will go into recyling and will get alloted to someone else. But since you are going on IR, 200 INR would be over in 2 month's rental :)

Activating IR
You can send SMS 'ACT IR' to 144 and get the IR activated. I would recommend doing this on the last day as it will cut 99 INR at that time. Vodafone says that IR is pre-activated and once you land in another country just restartin your phone will give the network and deduct 99 INR. I didn't want to take a risk so I manually activated it.

In Singapore
I have been getting network from Singtel and Starhub which are major players here. There is no problem with recieving the network here.

Rates on IR in Singapore
You can get roaming rates by sending 'ROAM SINGAPORE' to 144. Below I have mentioned approx rates:
Making a call in Singapore - 16 INR / min
Making a call to India - 95 INR / min
Recieving a call - 64 INR / min
Sending an SMS - 13 INR / min
Recieving an SMS - FREE
Right and this is what you can use your number for! Just keep recieving SMS from friends and call them back as needed ! !

Solution II
Put our number in safe custody. I am not sure if all service providers have this fascility.

Why?
If you do not use your number for 6 months continiously, it is sent to recycle and will be alloted to someone else. To avoid this the number can can be put in safe custody with nominal charges and you can resume using it with our existing plan when you come back to India. In this conditon, one cannot call/recieve phone calls or SMS. So it is like a dormant state.

Procedure
You will just need to submit a written application to Vodafone for activating this. To deactivate, you will need to give the written application again.

Rates
It costs about 100 INR to kep your number in safe custody for 3 months. This can be extended as per needs. The also have plans for of 1 month to 1 year. Rates can be confirmed with Vodafone gallery.

Solution III
Surrender your connection. This is as simple as it sounds. Clear your bill and submit the number and put in a claim for your deposit.

My reason for using Solution I
I have an iPhone and I can send SMS free through internet (by using WiFi which is easily available) to any number in India :) You can converse frequently by using SMS as it is a local SMS for your friends in India. But yeah at the end, choice is yours.

Mobile Phone
Well, you dont need to change your mobile phones while reocating to Singapore. The GSM services in Singapore have the same frequency bands as India. So all you would need to do is buy a connection in Singapore, put the sim card in your current phone and start talking.
But obviously if you fancy a new phone, I will suggest you to buy it in Singapore for price adavantage.

iPhone users
Yes, I have an iPhone which was purchased from Vodafone which is not available in Singapore. I was very dissappointed as I would have had to give it to someone in India to use it as this was locked with Vodafone India. But thankfully the unlock is available for iPhone 3G 2.2 Fimware now :) For more details you can mail me or just search for 'yellowsn0w unlock' in google. But since I would have 2 connections (1 India number on IR and 1 Local Singapore Number) I am carrying my good old Nokia N-Gage with me!