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Jorrit Jongma
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Hot air balloon ride
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Ik heb een paar jaar geleden een luchtballon vaart gemaakt. Geweldige ervaring! 
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Jorrit Jongma

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Oh yeah!
Pry-Fi released (root required)

You are being watched...

Retailers, crooks, the government, and others shady individuals are tracking your movements. Even when your Wi-Fi is turned off, your phone may be broadcasting information to whomever is in range which can be used both to track repeated visits to as well as your exact movements in an area under surveillance.

It's not a big step to couple this to personal information - a retailer for example, could track your trip to the register and correlate with your payment information. Now the tracking hardware and software vendors, the store (or chain) owner, their business partners, they can now all track where you are every time you come into range of one of their systems, and fully profile who you are, what you do, your financials, and your daily patterns! 

That is just one example, but there are many uses for tracking you. Make no mistake, this is happening in the real world today.


One solution is shutting off Wi-Fi completely (including the background network scanning, a setting most people don't know about), but you would lose benefits like automatically connecting to known Wi-Fi networks and improved location awareness for your apps. It also does nothing to help the situation for others.

Pry-Fi will prevent your device from announcing all the networks it knows to the outside world, but it will still allow background scanning and automatically connecting to Wi-Fi networks. While you are not connected to a Wi-Fi network, the MAC address will constantly be pseudo-randomized, following a pattern that still makes the trackers think you are a real person, but they will not encounter your MAC address again. This will slowly poison their tracking database with useless information.

When you do connect to a Wi-Fi network, unless you specify otherwise, your MAC address will also be randomized - the same MAC address will not be used the next time you connect to this or any other network.


Though of course the companies involved with these trackers claim they wouldn't use the data maliciously, the possibility is there, and we all know that if something can be abused, ultimately it will be. There do not appear to be any laws against these practices yet, nor is it likely Wi-Fi will be redesigned any time soon to get rid of the information leaks.

But we can make an effort to reduce the usefulness of the tracking data for the exploiters. Pry-Fi comes with a War mode, which when enabled tries to make your Android device appear like dozens of people. Just wandering around an area under Wi-Fi location surveillance for a few minutes can ruin the tracking data for the period of your stay.


This is proof-of-concept code, and how for it will go in the future depends on interest and how well it works. It has been tested on several devices and seems to work, but it is very young still. The magic the app does to achieve its purpose is ever subject to changing Android security policies and OEM customizations, so even though it works now, there really is no saying if it will still be possible in future firmwares.

Of course you should also keep in mind that tracking can be done in many ways, and these W-Fi signals are far from the only method in use.


Further details, device compatibility information, FAQ, discussion, etc is all available on here:
The description for this app is currently being written. Check back in a fe...
Jose Fuentes's profile photoGijs Wiggers's profile photoKowalski OmniROM's profile photoDiego Vargas's profile photo
Amasing man now m invincible in ma office
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Jorrit Jongma

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iOS teaser

I'm just going to leave this here ... (and run off to unpack presents with my family)
Jesús Ramón Alvarez Félix's profile photoAC POWER COMFORT INC's profile photo
Hi Jorrit, excuse me could you bring more information, a pre-release or sell this working for ipad jailbroken mayor thru cydia?? please I really need this on my ipad, maybe also working with EasyCap.
Thanks in advance. 
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Hmm comets!
As Thanksgiving approaches, Comet ISON enters the final stage of it’s loop around the sun. What does this mean for us?

Thank you to +The Huffington Post for such an awesome graphic!

#ScienceEveryday #Thanksgiving   #CometISON  
David Gross's profile photoMiguel Ángel MF's profile photoAlex Gonzalez's profile photoPatrick Hill's profile photo
The sky is falling! The sky is falling! 
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What do Cookie Monster and Offline Disk Import have to do with one another? Check out how our OmNomNom machine makes offline disk import fast and easy:
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Me eat more coookkkiiieeees....
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Jorrit Jongma

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Yup :)
Announcing DSLR Controller Wi-Fi Stick

It has been a while coming, and now it's finally here - the customized version of DSLR Controller you can run on a cheap  Android TV stick to create a Wi-Fi module for your Canon EOS !

Now you can make any supported Canon EOS camera Wi-Fi capable, and you can control it with your Android phone or tablet running the normal DSLR Controller app from a distance !

Unlike other solutions with profit margins approaching entry-level camera prices, this solution can be up and running for about 100 USD !

More details are available on the DSLR Controller website (see the box below the post)


Please actively help me spread the word - as DSLR Controller is an Android app instead of an iOS app, most photography news outlets mostly ignore it unless a lot of noise is generated about it. I appreciate your help!

As for DSLR Controller itself, there will be a fairly major within days!
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In his circles
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Jorrit Jongma

Development  - 
Pleasantly surprised with how easy the GDK is to work with. Good stuff.
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Corey M
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Jorrit Jongma

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Happy New Year !

Here are some pictures I took of the fireworks from a friends' balcony on the 15th floor. My first attempt at capturing fireworks (after ample beer and champagne), and hardly post processed (ain't nobody got time for that), but some of them aren't half bad. The humidity didn't help much, but I'm just glad it wasn't really raining, or heavy fog like last year.

Learned a lot about photographing fireworks in this attempt (better next year!). I thought I'd be using a wide-angle because I was in the middle of a fair-sized city, but ended up mostly using my 70-200 at the 200mm end. Most exposures were fully manual f5.6-f7.1, 2.5s-4.0s, iso200-iso400.
Chainfire's profile photoJean Marth's profile photoHassan Kazmi's profile photoAC POWER COMFORT INC's profile photo
Wow! Amazing happy newyear too
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Jorrit Jongma

General Discussion  - 
In case anyone wasn't yet aware of this ...
OpenDelta released and integrated into OmniROM

If you're an OmniROM user on one of the latest nightlies, you might have noticed that suddenly, wild System Updates have appeared, courtesy of OpenDelta.

OpenDelta is an OTA / delta updater designed to keep your ROM up-to-date while downloading as little as possible. If possible, it will download only the changes between your currently flashed ROM, and the latest available one, greatly reducing the download time and size.

Delta en/decoding is based on the VCDIFF (RFC 3284) standard, and is provided by the OSS xdelta ( )

OpenDelta is fully Open Source and license under the GPLv3. Any open ROM can use it. There are various configuration options present in the config.xml that your ROM's overlay can override to use your own servers and deltas.

Keep in mind this package is really new, and just now rolling out to a number of devices - there will still be some snags here and there!

The link below leads to the OmniROM GitHub, where you can fork the project if you want to. Submitting patches should be done through Gerrit ( ).
Xun Luo's profile photoThiago Tardelli's profile photoJovan Philip's profile photoMuhammad Najmi Ahmad Zabidi's profile photo
+Thiago Arzobispo open super SU app, last tab on the right. 
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Jorrit Jongma

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A small selection of pictures from my holiday to Costa Rica this summer. Hot and humid, so I didn't bring the big and heavy camera everywhere, and the natural lighting was always bad (dark nature due to jungle, overbright skies due to summer sun) ... but still some good ones, I hope !
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Que buenas fotos!!!
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Jorrit Jongma

Discussion  - 
The latest firmwares for the GT-I9505 Galaxy S4 LTE have SELinux enabled and set to enforcing by default. These are official retail firmwares that will be available for download by normal end-users through KIES or OTA updates. The Samsung Unpacked event today put a bit of emphasis on their KNOX security package, possibly this is related, as these firmwares were also released today.

The firmware I personally played with (available from were all marked I9505XXUDMGG , though others say ...H8 also has this.

Thought some of you might want to know about this development, and poke at it. I haven't run into any (non-root) apps that had any problems with it yet, so it seems to be fine so far.

su calls are detected and you get a nice little popup which claims it stopped some process, but it really hasn't. With some adjustments, SuperSU was made to work pretty much as it always has.
eagle wings's profile photoMark Manning's profile photoGregor J. Rothfuss's profile photoJorrit Jongma's profile photo
Sure, there may be a problem in the future if they update. They are monitoring more than the binary name, I've tested that. I'm not sure what call triggers this popup. I do intend to find out, but I'm going to hang back with that until there are kernel sources for a KNOX firmware, as it will probably be much easier to find.
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Jorrit Jongma

Discussion  - 
Quoting myself, because somebody has to do it ... ;)
nosuid on 4.3 isn't the su-killer

There's been a lot of talk about the nosuid flag on mounts, that this prevents Android apps from executing things like su. While in the standard su setup this is certainly true, it doesn't really matter, and isn't the big reason SuperSU went daemon/proxy.

nosuid is (in the way it is currently setup) trivial to circumvent if you can run stuff at boot as root, as is the case with any flashable/rootable device. In other words - for root uses, it's not really relevant at all.

What is relevant, is the capability bounding set. Most processes (including all normal Android apps, and adb shell, and ...) have these severely limited. As a result, even if you have the (old) su binary installed and you could run it, you would indeed get root user. You would however still be completely unable to do anything interesting like remounting system (as just one example). As such, it may have seemed that the (old) su binary actually worked from adb shell - but it wasn't practically useful.

To read more about the capabilities as referenced here, and what you can and cannot do with them, see this page here: . Previously, most processes had all of them. In 4.3, most only have CAP_SETUID and CAP_SETGID available, with the all-important CAP_SYS_ADMIN being missing.

That's the big reason I'm still using daemon/proxy mode for 4.3, not nosuid.
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Thank you +Jorrit Jongma.  I appreciate the explanation!
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In his circles
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May 6
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