Why I'm reminding you some old SDK, which is nowadays practically dead and forgotten? Because I hope that from one point of view it's still pretty actual topic...

I recalled it few days ago. I was working on a small petty project which uses CObexClient class for transporting OBEX objects. The problem is that when receiving side gets information with request for Bluetooth connection it can decide if it will accepted it or not by pressing Yes/No CBA buttons on pop-up dialog. But when no button is pressed API doesn't allow canceling request on sending side...

After finding out such problem questions are arising... Is it bug in API? Are there some good reasons for it? Is it part of closed API? Can I as PRO member pay for obtaining some hack solution, access to API or simply for answer "no it's not possible"? As usually it's not so easy to find a truth and solution.

But in the past there was also one other chance - there was possibility of checking other vendors SDKs and the truth is that Sendo-X SDK opened the Symbian API more than Nokia did and sometimes it makes possible to implement requested functionality. In the case of my problem with CObexClient it helps me a lot.

I don't want to judge Nokia (or deal with legal issues) - they're doing a lot of good things for developers. My problem is that I'm just little sad that variety of Series 60 devices disappeared. Where are Siemens SX1, BenQ, Motorola or Panasonic devices? It's a pity that instead of increasing number of licensees, devices and consequently also SDKs from different vendors they said farewell to Symbian business and the only big warriors who survived on the battle field are Nokia with domination on Series 60 platform and SonyEricsson with their UIQ devices. I'm sure that diversity makes the position of Symbian platform much more stronger and it's good for everybody: for developers, for customers and also for vendors, because they must confront and deal with competition...

Rest in peace Sendo-X SDK!

Regards,
STeN

I remember one shocking moment from my childhood, which was recalled from a dark place in my memory not a long time ago... One sunny day command line antivirus tool running on my 286 IBM PC simply announced that the computer is infected by Yankee Doodle virus. It played hymn every day at 17:00 on my crackle speaker. I panicked, having no idea what and how to do. I was ready to make a deal with devil to know how to solve my situation. Sounds funny? Since this incident years passed, but history likes to repeat...

From that time floppy:) boot and COM/EXE infecting viruses become history and new types of trojans and worms spread by mails and badly configured or unsecured network services emerged. With growing Internet also various spywares and adwares caused more and more troubles to connected users. I had almost always some antivirus or anti-spyware tool installed on my private Windows desktop and in the Linux environment I simply don’t care. Being employed also means that my computer was connected to the trusted corporate network, automatic content checking service was usually installed on the mail server, firewalls cared of disallowed network connections, automatically updated antivirus and patches were installed almost every day and whole system was maintained by some special departure, so one can practically forgot completely about virus danger and I stopped caring about it completely.

What was my surprise, when less then a month ago my teacher of russian language noticed that I have Symbian phone asked me, why I bought a phone, which can be so easily infected by a virus? At the first moment I was thinking that he makes fun of me, but sonly I found that he's really serious. I tried to explain him that:

*  It's not possible to copy a virus by MMS or Bluetooth without his knowledge.

* I confirmed that there's plenty of harmful software, but question is if we could count those Symbian programs into virus category, because they're not able to replicate itself and infect other applications until now and phone display few pop up dialog every time you install the new software.

* I also said that he can fall in potential danger only when he'll download cracked software from warez sites or he'll try to install freeware from untrusted sites, torrents or simply company intranet share folders...

 

I'm not sure I persuaded him, but it makes me wonder if the situation is really so bright as I explained, maybe it's really time to install antivirus software now. I think practically nobody cares about possible problems and checks installation sis files before unpacking then to tne the phone and then when such people fall in troubles the myth of Symbian viruses can grow... I searched Internet and I found that it has caused considerable discussion, so I decided to try as many Symbian viruses as possible and put my observation and experiences to this blog site. That's what the next part of this article will be about.

I'll try explain how those viruses  work, put some source code here and try to rebut the myth called "Symbian virus".

Another Symbian Smartphone Show will take place in London after more then three months, between 17^th ad 18^th October. I think for everybody it's worth to be there just to look around or make some personal contacts. Organizers promise over 120 exhibiting companies, 60 free seminars, and over 3000 attendees from the entire smartphone industry.

I hope that at least some Nokia Champions members will come here and we will have chance and opportunity (e.g. during last day?) to meet unofficially together in a friendly atmosphere in some pub aside main busy London streets to have a beer or glass of wine and talk...

Perhaps you already know each other, because Nokia proposed us participating in many interesting events during last half a year, but I personally have no time and sometimes also recourses to travel across the world to those meetings and I also don’t know if you participate. So if you want to meet, just send me a comment and we could organize it together in some way.

See you in London...

 

I'm thinking about utilizing much more from cell and location information available on Symbian phones than it's done in any current application. Based on information I have, and I hope you'll correct me if I'm doing wrong, with today's public Symbian OS API we looking through keyhole into room full of treasure - possible amazing applications - but we haven't key to open the door - we're missing proper API to access the NMR (Network Measurement Results) data...

 

From the time I decided start development on Symbian platform I heard from numerous people similar questions related to the Symbian GSM location functionality and to be honest every time I answered them I was not really sure what to say. I will not try to describe here GPS, E-OTD or other advanced systems, which needs additional support from phone device SIM card (SIM Toolkit solution), MS or network hardware or software upgrade. Those systems are not available to everybody today and solution driven by operators (with the problem that they could vary across the world) will never allow to single developers to participate in. Let's aim our effort only to abilities of normal smart phone available on the market. Crucial question we had to answer and I hope once again, you can help me is: Even if will have all NMR available on the phone, will we be able to measure mobile position with 10 meters in micro and pico cells areas up to 100 meters in large areas covered by one BTS? There is a lot of materials describing mathematical models (quite difficult to understand:) and theory, but how it's in practice?

 

Reality is that every mobile phone user can easily search the Internet for information about "Net monitor" or "Field test" applications, which were in different ways hidden somewhere on the phone, before normal blind users. Those application were not useful for masses, but they at least show us what could be monitored by the phone API, because  there was always someone enough skilful, who found how to activate and run those hidden menus (on older phones) or standalone applications (on some Symbian devices) and reveal this secret to others. Let's left out for now question if such activity is legal or not. In any case result of those activities is that it's clear to all programmers that applications developed by phone manufacturer could have access to the information up to six or more neighbors cells and can obtain data about signal strength and others from the mobile network. More precisely it was known of course, that GSM device must have access to such information, but those applications show how easily it can be done and put into life many new ideas, how to use them.

 

Awareness of location is important part of context sensitive services, actually it is probably major factor comparing to other information as temperature, biometrics, etc. I personally think that information about six cells reception levels (signal strength), their CellId or BSIC (code is at all times transmitted on the broadcast channel, so the Mobile Stations can distinguish between base stations) possibly enhanced with access to the database with measured BTSs' GPS coordinates, measurement maps of their coverage areas and information about their power, could be input for more or less exact algorithm for estimate mobile position. Especially in the case of micro or picocells the information can be quite accurate. The signal strength is affected of course by terrain profile and building construction, but measurement map could help to solve the problem. Additionally also TA, but only in large areas (Timing Advance - because of different distance between MS and BTS, this value counted by BTS is used for synchronization when data bursts are send from MS to BTS) could be used for measure the distance from BTS. All mentioned information are available on GSM phones and the maps and databases could grow rapidly if there'll be demand for them. We cannot expect that operators will give us the information about their network, which is considered as sensitive information to be kept in secret, but groups of BTS hunters collect such information (this activity is naturally legal) and put them into freely available databases. Keep also in mind that a notable part of location based mobile application could be used only locally (i.e. Madrid tourist mobile guide), so it decrease demands on databases size and its costs.

 

Let's now have a look on the most obvious examples of location based services: Determination of your small child movement, triggering action with the fact of leaving predefined cell, downloading SVG map with you position marked on, navigation and guide for tourists in foreign cities, location based games, location of the nearest fitness, car service or restaurant, emergency and law services, collection statistical information, monitoring company truck drivers, etc. Doesn't it sound interestingly? The accuracy (average about 100m) of cell based position is not comparable to GPS solutions of course, there will be still some doubt on exact position, especially in the macro cell areas covered by powerful BTS, but on the other side GSM signal is available also inside buildings and heavy developed city centers, tunnels and other places, where its precision increase rapidly and where GPS cannot be used. If anyone try to monitor how fast are BTS handling the phone changing in the centre of the city, will probably agree with me that having such information could be quite useful.

 

Unfortunately having similar functionality as the mentioned "Net monitor" application and using it in some reasonable way is not possible, because necessary API is missing. There were some tries to reverse engineer the way how this built-in application works, but for the first I'm not sure if this is legal and for the second it failed on newer devices and it cannot be referred as general solution. I don't know why cell related information are not available for developers. Due to some information I found on Internet, network providers made complaints to phone manufacturers on easy "Net monitor" enabling, so users could measure signal strength, and consequently similar applications were removed from phones, additionally operators provide their own location based solutions and probably they want to competition, who knows?

 

For all of that if you search Internet you'll find plenty of small products, which use cell information as CellTrack, MiniGPS, CellSpotting or popular game called Journey. You can find also many projects and hundreds of pages, studies related to this topic.

 

Maybe some of you wonder how applications listed in previous paragraph work, when I already said that cell monitoring is not possible? Well, there were many Symbian SDKs available in the past and putting together header files from old Nokia 9200 with export libraries from Sendo X makes possible use API for getting information about current serving cell. This approach still works with the 8.0a FP2 SDK, but I expect that on the newer Symbian v9.1 it won't be possible, but I didn't test it yet and I also didn't check if there isn't any new method how get similar information.

 

Now if you read my article to this point, please try to give me the answer why location related information are hidden and are not part of public API or just put write your opinion.

 

Thanks for reading.