There are two widely known methods of installing Java applications, and you can use the one that suits you best. The first one implies that your phone is Bluetooth compatible with OBEX standard and that you have a Bluetooth dongle that you can insert into your PC (MAC owners don't need that).
If your handset doesn't have an embedded File manager, you will need to install Fexplorer to be able to transfer the data to your mobile. Java applications are known to have the file extensions .JAD and .JAR, and you can install either of them, but not both. However, bear in mind that there are certain models that only support .JAR file types.
After downloading the desired application onto your PC you can transfer it to your phone, as you can see in the screenshots, using Bluetooth File Transfer Wizard. You can also use any other third-party software compatible with whatever OS your computer is running. The idea is to make a Bluetooth connection between the phone and the PC. The phone will receive the file under the form of a message that you can choose to save (if it's a music or an image file) or install (if it's Java compatible).
Open the newly arrived message and choose to install the application (game) that you just sent through the Bluetooth connection. I recommend installing it on the memory card (if you have one) in case you have a low-memory phone. This will probably take its toll on the speed of the device when you open an application installed on the memory card, but you'll have more internal memory left. Of course, you can place it in the phone's memory if you want fast booting times for your apps.
For the second method you will need a card reader, a phone that features a memory slot card and a memory card. Put the memory card into a card reader and place the Java application you want to install on the phone in the root directory. Do not put the file into any directory, unless you are certain that your phone can read it afterwards. Pull out the memory card and insert it into your phone.
Start the File manager that you previously installed (Fexplorer) and go to the location of the file on your memory card. Click it and the installation process will start. After you're done you can delete the .JAR file from your memory card in case you need space.
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