It is against the Law, to use mobile phone without IMEI number.
You must have registered your SIM with the carrier under your name, NIC number and address.
A person can have maximum 5 numbers of SIM cards only, from a carrier under your name.
It is against the Law to use a phone with the SIM that was registered under another person's name.
Don't use mobile phone when driving or walking as it is against the law.
Do not take photos or videos in restricted areas and in front of (disrespecting) the Buddha statues. (Violation may lead to criminal prosecution).
It is not allowed to take photos near to a running train.
If the phone is lost or stolen report it to the nearest police station and get a copy of that police entry and report it to your carrier along with it and get your new SIM card. And then report it to Telecommunications Regulatory Commission of Sri Lanka along with these documents.
TRC will assist to recover the phone or will make it unusable. But you can't contact them directly or lodge complaint about the lose of phone.
Don't buy mobile phones from unknown people to avoid legal problems.
The CDMA phone connection is meant for to be used in the registered address only.
CDMA phone can't be used as a mobile phone as some people carrying it in their cars and vans. It is against the law.
Reload Smartphone with call minutes and data plan separately. Using calling minutes for data plan? It will be expensive than the data plan price.
Beware of free Wi-Fi hotspots as they may plant tracking scripts in Smartphones, when you happened to connect to the internet through their Wi-Fi Hotspot.
Always keep your phone's Bluetooth setting in "off" position as some people try to send scripts to control your phone. Switch it "on" whenever in need of the Bluetooth activity.
If you are getting unwanted calls and/or SMS to your mobile phone, complain it to your carrier and to the local police.
Using Smartphone's "Block Call" App can stop these annoying calls and SMS text messages.
Don't open MMS and SMS text messages that are coming from unknown people as they may contain malware or scripts to control your Smartphone.
Always try to reload more than Rs 500/-, if you gave a wrong number, you can recover that money with the assistance of the re-load provider.
If you are using a Smartphone, install "locate my phone app". This will help you locate your phone in case it is missing.