Android platform, can I meet those requirements?

Folks, I'm trying to see if my plan realistic at all. I'm ne to Android platform but not new to software development. This is my first post here as well :)

We want (in our company) to create Android software to compliment our truck management software. Basically, it will do couple very specific tasks.

a. Send GPS updates to server. b. Receive trip information. c. Send pickup/delivery confirmation to server.

After evaluationg i. platform and Windows phone 7 platform we came to conclusion that only Android has multitasking that works for us. So, Android it is but I have some specific questions.

1. Data plan we want to use will be very limited. Probably 5M/mo and no voice/text. I figured 5x1024x1024 = 5242280 bytes will give me 1k per transmission every 15 minutes (3000 transmissions per mo). It will leave 2M for other stuff that will happens every couple of days. Does my math look OK or there is lot of "waste" traffic? Our server going to be XML SOAP and messages sent will be just Lon/Lat in XML package. 1K will be OK? If I just calculate bytes it will be even less but I wonder if there is "minimum" packet size, etc. Any insight on this data limitation appreciated.

2. Because of #1 we need to "lock" device somehow so there is no other software that uses network. Possible? If so, what do I need to look for? I found already created app - firewall and it says phone has to be rooted for that.

3. Receiving trip information. What's the best way to accomplish that given my situation? Should I run some kind of listener? Will my phone have IP address or something? Or should I get small text plan and use that for this specific functionality? Can I receive text message in my own application?

So,开发者_JAVA百科 as you see we trying to shrink $80/mo service to $15/mo service that will do big savings to our company but not sure if it's all possible with constraints we have. Also, we may just give discounts to drivers who have Android phone and will install our app but we don't count on that.

Thank you in advance for any help on this subject.

UPDATE: Now that I think about it - limited data plan present challenges initially but actually helps us do it "right" to make sure we don't overload server with constant polls. What I really like to see is some real-worls experience with data usage. Problem is, to us to even come up with test app - will require considerable effort. Would be much better to rule this out right now if it won't work. For example, if I knew that message size 2k no matter how big of a message itslef - then I would know immediately that it won't work for us..

If you have a very limited kind of data that you are transferring, the overhead of xml might be unnecessary. Instead, pass .csv data to different endpoints dependent upon the data that your are transfering (one endpoint for lat/lon, another for pickup/delivery confirmation)

You do have an ip address on each device, but you're not necessarily going to know that information - it's not constant, or consistent (it can change as the phone moves around). Instead, do a timed polling of the server (that would make your 3rd endpoint) See other mentioned solution of triggering on SMS.

As far as locking the device, I'm not sure about this, but it certainly seems feasible (though it's not consistent with your 'discounts to drivers who have Android phone'. I understand why, but if the phone has no voice/text capability, it's not likely that the phone will be used by the drivers for much besides it's expected purpose.

You are not going to achieve this with a default Android ROM in other words you have to create your own customized ROM from scratch and deactivate quite some stuff in order to get your devices not to use up the 5M/Month.

You can checkout the developers site on the Android source code to check out if that would be an option for you. Giving discounts to drivers owning an Android phone sounds nice and all but I'm quite certain that this is not going to get the desired results which I guess are that you equip all your trucks with such a device and track all of them.

In my opinion it is not going to work with a data plan of 5M/Month but on the other hand I don't know the data consumption numbers without testing.

UPDATE: Also I would not go with XML but with JSON due to overhead.

When you upload a GPS update, have the server reply with any of the trip data you need to push down to the phone at that time.

I think that for the data traffic (the other topics that you asked about are already solved in the other answers) using a bitmask-like solution will be the best option, first bits are for lat, the next for lon, and then some bitmask for the flags, and sending text data only if it is necessary.