One of the functionality that makes the Android stand out is its multitasking ability, meaning you can run many different apps at the same time. With many apps running in the background, you'll start to notice the decrease in performance. You could always restart your phone to close down all your unused apps, or download Advance Task Manager application for the Android. By closing apps, not only do you get an increase in speed but also save a lot of battery.
If you have root, Masqed Crusader will be able to help your Android browser to load up a little faster. What this application does is that it will cache the server name cache so that there is no reloading of the same website, if you have already visited the website before. Masqed Crusader will only work with the stock browser found on the device and must be activated on startup.
For non-rooted users & rooted users:
It is well known that the stock browser is slower then many of the browser applications available on the market. Pcworld has done a great review on android browsers, to conclude that SkyFire is the fastest of them all.
When it comes down to it, emulators are legal as long as the bios is not provided with the package. Roms on the other head, are illegal to download unless you have a legal copy and/or ripped the rom out yourself. Now, why would google start to remove those emulators? The main reason would probably be legal pressure from the gaming companies.
Sony, Nintendo, Sega and many others have recently began to reintroduce older titles into the smartphone application markets. As a consumer, no one would want to pay for what is readily available on the market. Thankfully, developers like yongzh have posted his app for free.
Want to see how some of the applications work? Now you can with android-apktool. You can now view all the codes and files of the apk files.
Description of the program: "It is a tool for reengineering 3rd party, closed, binary Android apps. It can decode resources to nearly original form and rebuild them after making some modifications; it makes possible to debug smali code step by step. Also it makes working with app easier because of project-like files structure and automation of some repetitive tasks like building apk, etc."