The cell phone is now a beacon, gps tracker, facial recognition system, keeps text and offers voice prints.
If a person is a journalist or meeting a journalist understand that just been near a journalist with a connected cell phone can be useful to track that meeting.
The ability to turn on the microphone is another issue.

In the past the local network dropped to an older standard depending on the version of the IMSI catcher and the network standard it used?
A few projects have been mentioned to help understand the local network conditions and then show the user changes.
Phone Firewall Identifies Rogue Cell Towers Trying To Intercept Your Calls (09.03.14)
http://www.wired.com/2014/09/c...

Re "Basically the keys to the castle without presenting any evidence that your doors are all open. as useful if not more so than UEFI takeover."
Ready to go after any wipe or AV or heuristics, behavioral analysis. Collecting data and waiting for a network or usb stick out.

Price and the design of the cell networks going back many years. The security services had a list of needs going back into the 1980's and for the UK it was all network use in Ireland.
As cell and sim systems advanced the security services just kept up with having total mastery of every aspect of all the different telco networks.
Now users and telcos have to consider who else has the security services methods? Ex staff, former staff, dual citizens, contractors, foreign contractors. People cults and brands able to pay for the skill sets of ex staff, former staff? Once a telco network is fully open to the security services other groups can buy or are given the same methods over the years.

Lets hope the certs for that end to end link are still good as offered :)
A lot of nations will now just go back to one time pads and number stations with all the junk Western networks used for quality disinformation.

The problem is tame junk encryption is really open to many ex staff, former staff, other nations, cults, faiths, rich people, political groups, anyone with lots of cash and a few contacts.
SISMI-Telecom scandal https://en.wikipedia.org/wiki/...
Greek wiretapping case 2004–05 https://en.wikipedia.org/wiki/...–05
Cell networks have a very low standard of local encryption thanks to weak junk international standards been set over many years. The results can now be see and understood.

Re "If he was sitting on this information, then why wait so long to release it? "
All the material is now in the hands of the press. The press can release the material in any way it wants or needs to.
Re "Could someone explain where Edward Snowden is getting these kind of leaks and infos from, so long after he fled the NSA?"
The material released by the press is long term generational projects staff get read into as they need to work on the same projects or with staff who do.
Re the how http://www.bbc.com/news/world-... "Edward Snowden: I was a high-tech spy for the CIA and NSA" (28 May 2014)
"...he said he had worked for the CIA and NSA undercover, overseas, and lectured at the Defense Intelligence Agency."

Re "... but do they have any other ability to use the data?"
Parallel construction or just keeping up on slag, street crime, terms, faces, people, voice prints, images sent, gps, serial numbers in each photo or video uploaded? A vast database of interaction, who is smart and turns their phone off, two people walking towards each other who turn their phones off before a meeting but where not understood to be connected until that deeper data mining uncovered their cell logs.
Locals find the locations, federal computers look over years of huge telco logs. Funding is hidden from a local walk in FOIA at a city and state level.

The cost of asking the phone company?
Letting a phone company flag or set a number been logged in a database. If staff or other nations have access to that phone company database then all legal wiretaps might get seen by a few different people or other intelligence agencies. The US seems to have found out over the years that it cannot trust its own tame telcos internal networking.

Yes all the paper files and audio tapes in the archives of Central and Eastern Europe from the early1990's should be a warning from history.
The West likes to collect too ;)

+1 for this. Divest from the tame brands that fooled generations with junk encryption.
Teach about the one time pad, number stations and other good encryption that works.
The whistleblowers over the decades have offered insights into how the telco networks work and how weak encryption standards are kept in place for generations.
"So long as the tame brands pretend to encrypt for us, we will pretend to communicate."
Get creative with local political issues and long emails to the local press. Fill the text with past stories about local events.
Drive around with an older working cell phone on random local events.

The part about a system of computer networks that protect dissidents, journalists, NGO's, faith groups, freedom seekers and other color revolution efforts could be open to law enforcement officials at a funding and skill well below an intelligence agency level.
If the anonymity and privacy on offer by onion routing for dissidents, journalists, NGO is trackable on domestic local enforcement budget then what are other well funded nations doing on their internal telco networks?
If the US at a police level can track all users on onion routing other what kinds of lists do other nations have or what have their domestic intelligence agencies found?
Public news like this sheds light on the low costs and ability to track onion routing. Down from intelligence agency to a state or city?

1+ for easily and percisely tag almost all photos we were able to stuff in it. In microseconds.
This tech is old for the 2d face work. Its fast for local police Privacy concerns? UK police test 'faster-than-ever' facial recognition software http://rt.com/uk/173292-facial... (July 16, 2014)
Or just read the public info on records per second in the 10,000 records/sec http://www.nec.com/en/global/r...

How is open code everybody can see, work on, understand and create with "a different monoculture?"
The past closed proprietary DHTML features?

+1 for this great suggestion. A good audio codec, video codec, encryption and emoticons. Clean new open code that works as a new instant messaging app :)