Installing MIDlets on Series 40 and S60

The MIDP specification allows quite a lot of variance in the installation procedure of MIDlets. The spec basically only states what the AMS (Application Management System) needs to take care of but not how it should be taken care of. So it is no wonder that installing MIDlets on Series 40 is different from installation on S60 phones.

First of all, when you transfer MIDlets to Series 40 phones, they will get installed "on the background". The user does not need to start the installation procedure and walk through the installation - after the user navigates to the Application menu, the MIDlets is already there. On S60 phones the user has click through an installation before the MIDlet is installed on the phone. If the MIDlet was downloaded using the browser that process starts automatically. In other cases the user has to go to inbox and start the installation by clicking the JAR or JAD file. On Series 60 phones the destination of the MIDlet varies across the board. On some devices the MIDlets are installed in "My Own" folder, or in "Installations", or...

On Series 40 phones the destination of the MIDlets has changed a little through the different models, but mainly the MIDlets can be found in the "Games" subfolder.

One might ask how Series 40 phone user knows which of his/her MIDlets are untrusted and which are signed as no installation notifications are displayed to the user. The answer is that the user has to select the MIDlet in question and check the MIDlet settings using the Options menu.

One thing to remember on Series 40 phones is that when upgrading a MIDlet, JAD files need to be used. If one intends to upgrade an existing MIDlet using JAR file only, the MIDlet does not get replaced but the new MIDlet gets installed next to he old existing version.

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