Project progress 2

Following on from a bit of a major rethink on my skills, I’ve decided to go with something mobile phone based. As I’m still quite keen to have something that can help disadvantaged people, I looked into voice synthesis so that SMS texts could be read out. Unfortunately, current Java voice synthesis needs a lot of memory, around 2-16MB and most mobile phones only have around 512KB although PDAs have 2-16MB so they would be a possibility. However, as J2ME isn’t a full version of Java, it doesn’t support javax.sound which all Java-based voice synthesis needs. I then looked into smart phones. As most of them run Windows CE, they have better memory management so ought to be able to handle speech albeit perhaps a bit slowly. I managed to find a synthesis kit for Windows but all development for Windows CE is done in C++ and I don’t think I would have enough time to learn it as well as turning out a major piece of work.

After a bit of a dump of things that mobile phones are capable of doing like taking photos, shooting video, connecting to servers etc, started looking into the idea of a skills exchange. When you need something doing, you use your phone to access a central database to find a supplier. When you do, a request is sent to their phone and when they do the work, they earn some credit in their account. The main problem with this, as with all skills exchange systems, is the good trades people will always have a lot of credit and if they can’t cash the credits in, then they will always have an excess. However the idea of an exchange system was still worth pursuing so I came up with the idea of a peer-to-peer system where users exchange “assets” on their phone such as video, photos, ring tones etc. Each user would register with a central server and log the assets that they have available. Other users would then browse the database and when they find something they want, they put in a request for it. The difference between this and the “normal” peer-to-peer networks is that the transaction is an exchange so each person has to be prepared to swap assets instead of just taking.

Over the Christmas break, I investigated technologies. For the server, MySQL and PHP seemed the most obvious and for the application on the mobile J2ME also seemed obvious. However, testing proved otherwise. I wrote a simple J2ME app that just called a script on the server. On 2 of my test phones it worked fine but on the 3rd which is Java-enabled, the app wouldn’t run. I believe it’s because it can only run MDIP1.0 J2ME apps and I’ve been using MDIP2.0. I did consider just developing for newer phones but as I have this “thing” about technology being accessible to everyone, I carried on researching. I came across XHTML MP which is XHTML for mobile devices. It calls a different doctype to render the page for the smaller screen and has a couple differences with normal XHTML but other than that, it’s pretty much a normal web technology. So far I have developed scripts for uploading and downloading assets to and from the server and have been able to use sessions for controling logging in. I’ve even managed to write a routine for browser recognition. With the system being mobile phone based, accessing it from a normal browser defeats the object somewhat. As typing on a phone keypad is not the simplest of things to do, the next thing to look into is the use of cookies. Again with memory at a premium, they will have to be stripped down to the minimum. I have already mapped the database out on paper so once I have got the cookies issue resolved, I intend to create the database and then work on the messaging system of alerting people when they have a request for a swap.