You can see a lot of applications tagged as free
Browsing, free game etc. Lets have look into its reality.

You must know how the word FREE is used. And before it what are the charges you are paying for. Of course you will get a net using charge with mobile bill, it is the sum of many sub charges.

The person or ferm making the file expect some return from it. Same as we pay a farmer for wheat( eg: opera mini) we can call it as MAKING CHARGE

The person or site holding the application and giving you facility to download it also deserve some money, same as we pay for a retailer( mobiles 24, ****** ,airtel.com)
We can call it as HOSTING CHARGE

Now the service provider who enables you to browse and download by using it, also charges you.
Service provider means the company which send you your mobile bills, or the company to which your sim card belongs to.
(Virgin, vodafone etc) called as TRANSPORTATION CHARGES.

Your internet usage bill include mainly These three sub charges
.
MAKING CHARGES+ HOSTING CHARGE+TRANSPORTATION CHARGE


Now the word FREE comes.

Free may means the application is free to download. Thats the MAKING CHARGE is exempted
But both other 2 are still there. Eg airtel home site.

FREE sometimes means the HOSTINGCHARGE also exempted. Such as in mobiles 24 but TRANSPORTATION CHARGES is not omitted

But the third kind of FREE means the all three charges are omitted.
(Its just a coincidence because different people decide the three charges,without knowing each other)

Now you may be also aware that the costs are going to different peoples.

Your tarif plan will decide about TRANSPORTATION CHARGES. For example, It may be one cent for one kb transportation,it will charge for browsing data
Like, 25cent for a 25kb webpage.
If you have a plan like unlimited TRANSPORTATION CHARGE free, (its generally known as UNLIMITED GPRS PLAN) then you don't need to pay the TRANSPORTATION CHARGE .
but still for unlimited gprs plan ,they(service provider) usually ask for a rent per month
So its also not free in literal meaning.
But with this plan you can download from mobiles 24.com, it will cost you nothing

Now you know that whichever the application you use to browse , it cannot garrenty the free browsing.

Free net using is only possible when it satisfy the three conditions,given below,

1 , MAKING CHARGE IS OMITTED
2 , HOSTING CHARGE IS OMITTED
3 , TRANSPORTATION CHARGES IS OMITTED

First one depend upon the developer . Second one depend upon the hosting site and the third one depend upon the service provider.
None depend upon the browser you use.