To access the internet as if you were actually in Malaysia, you need a Malaysian IP address. I can see two potential uses for this, but this does not mean you are limited to just those. It's pretty easy to change your IP, both on your smartphone and your computer.

Use #1: Access Malaysian Websites

Probably the most likely reason you want an IP from Malaysia is that there are some websites that are blocked outside of the country. This is common. Any search on the search engines will turn up results from people asking questions about how to get an IP from different countries. Some people want to stream football from Brazil, others want to access streaming movies from The US. Some need a Chinese IP to unblock Chinese sites banned in The UK, and others may need an Australian IP for some reason. There are many more, and Malaysia is no different. There's bound to be local streaming sites that are blocked or very slow outside the country. Having a Malaysian IP while connected to the internet will unblock them.

Other than actually unblocking sites, you can also consider that if you are Malaysian and outside the country, having an IP from your country can help you maintain the 'status quo'. I'm from the US and whenever I try to access my PayPal account or some other business related accounts, red flags and filters are set off because my IP has changed. To some websites, it may seem like I'm a spammer, or my account has been hacked. The problem goes away when I change back to my US IP. The same would happen for you and your Malaysian accounts.

Use #2: Privacy

Some internet users may need a Malaysia IP address for privacy. Because some western governments like The US and UK have deemed it necessary to start online profiling and seizing ISPs servers for various agendas, some internet users have decided to virtually move to another country. You don't have to pack up your things and go though - by virtually tunneling your data to a computer server in another country, you can virtually reside in a different country. For example, I could live in The US, connect to a server overseas, and be a 'netizen' of Malaysia. Options are not limited to this one country however - there are service that operate in hundreds of countries around the world.

How to change your IP

The best way to change your IP is with a VPN service. VPN services have VPN servers in different countries around the world. When you sign up for their service, you get access to servers in one or more countries, sometimes up to 50 or more. Though how many servers you can access and how much it'll cost you per month will vary, there are some things you can expect from most VPN services.

For fast browsing and streaming with your Malaysian IP address, I'd suggest a PPTP style VPN. This is available anywhere and can be used with most devices, including Mac, Windows, Linux, iOS, Android, and Nokia. For good encryption on smartphones, use L2TP. For good encryption and privacy on computers, use OpenVPN. Some places may offer SSTP, which is similar to OpenVPN, but limited to Vista and Win 7.