It uses a simple 5x5 grid of squares to represent a unique pattern that is used instead of a normal text 'password'.

GridLock automatically locks the device whenever the machine is turned off, to unlock it the user taps their unique pattern onto the grid.

Update Description:
v1.32:
- TJ37 fixes + soft reset bug fix.

v1.31:
- Fixes OS 5.2 problems.

**** [Jun 12, 2005] by Ivan
Good app. I would suggest the option of when to activate and also the size of the grid.

**** [Jan 7, 2005] by Rip Washington
Downloaded the freeware version today and so far I'm reasonably satisfied with it's performance, though I'd be hesitant to use it without taking certain precautions like backing up the contents of my pda onto an expansion card (hence the 4 star rating). The user's manual says this about the Pro version: "When enabled GridLock will prevent anyone from unlocking your Palm after a certain amount of failed attempts." Excellent security...unless for some unknown reason YOU'RE the one prevented access. Anyone who's used a pda for a while knows they occasionally become prone to crashes and system failures when aps fail, conflict or don't respond as they previously had. Just last week, many Tungsten E owners (myself included) welcomed the new year with the INABILITY TO KEEP THEIR PDAs TURNED OFF. This was due to a flaw in the calender ap's reminder settings. Not too hard to foresee an unexpected occurance where the pda is locked and will not respond to a soft reset, forcing the user (if he's lucky) to do a hard reset thus losing all data on the pda. I like it, but again, I use it with reservation.

* [Dec 21, 2004] by olaf
I have a palm iiixe. With palm os 3.5.2 it works properly, but after having installed palm os 3.5.3 everytime when i want to shut off my pda it resets.

***** [Oct 21, 2004] by Harry Teicher
Very good! I second the proposal that contact information on the opening screen would make this the perfect security app!

***** [Sep 9, 2004] by Nick A.
I love it! The only improvement I'd suggest is that when it displays the grid upon power-up, it also provides 2 lines at the bottom to put your name and contact number in case someone finds it. Otherwise, great program.

***** [Jul 10, 2004] by Dillon Robinson
Great, easy and works perfectly on my Zire.

* [Jun 17, 2004] by J.Pinkham
This installed fine on my Visor (PalmOS 3.1H3), but after it was enabled the visor just kept restarting, showing me the palm logo and restarting. I had to do a hard reset and restore from backup.

* [Apr 26, 2004] by Andrew B
Version 1.31 does not work for Tungsten C. It gives a Fatal Alert @ Emul68KMain.c, Line:403, illegal instruction 0EF0 at address 00000014, then requires a hard reset to fix.

**** [Mar 9, 2004] by SnOOker303
Worked on my Sony NR70v but NOT on my Sony NX70v!!! So it has NOT full OS 5 compatibility...

***** [Oct 7, 2003] by Carl (Geneva, Switzerland)
It does work with Treo Smartphones - I had a Hack which was causing GridLock some troubles.

*** [Oct 3, 2003] by Carl (Geneva, Switzerland)
Great idea, but... "GridLock is compatible with all Palm devices ranging from OS3 to OS5." Doesn't work with Handspring Treo Smartphones (OS3.5H4).

***** [May 29, 2003] by Dave
Love it but the documentation should tell you that if you pick your own turn-off time, "Power" no longer locks the unit (TREO 90). With no turn-off time, it *does* shut off (about 5 minutes) and the power button locks it too. I like the 5 minutes so I'm a happy camper!

***** [Dec 14, 2002] by Evan
This amasing little App is the EASIEST security App I have ever tried!!!!!!

***** [Sep 11, 2002] by Omar
This is the best security program available so far thank you. Este es el mejor programa para seguridad de su palm pilot uselo.

* [Sep 8, 2002] by big g
Doesn't work for my m125.

* [Jun 20, 2002] by Cinth
Does not work with visorphone on the handspring platinum.

***** [Jun 17, 2002] by JC
Great app! I had a line of co-workers waiting for me to beam it to them after doing a 5 second demonstration. This makes it simple to secure your Palm, no clunky text passwords.

***** [Mar 26, 2002] by Dennis Khaw
Excellent program!! I have used this for about 2months now and it is so easy to use. At only 16K it uses so little memory, yet provide so much security.

***** [Mar 10, 2002] by Jack Wodke
Did a Back Flip for this Grid Lock..So easy to use and works fine on my Visor. Deleated all the rest of security programs.This ones it for ease of operation and simplicity. Thanks, Jack

**** [Aug 7, 2001] by CRE Broker
This is a great app, one of the best for security - very simple and doesn't involve graffiti! Unfortunately it is no longer freeware - a nag screen comes up every so often.

*** [Jul 31, 2001] by Lock
GridLock is a wonderful application. Too bad, it's no more freeware... :\

***** [Jul 5, 2001] by Robert Haack
A great security program for those graphically oriented. Nothing compares to gridlock where one can simply remember a pattern to unlock your machine. Highly recommended....

**** [Jul 3, 2001] by Løck
Wonderful program, really great. So far I found only a small problem. Let's say that I set 5 appointments then I lock my Palm. During the day these appointments ring but I simply press ok and I turn off the device. Well, in the evening, if I turn on again, I've to insert the "GridCode" 6 times, one for each alarm and one for access. I hope this will be solved in version 1.2 Anyway I suggest this program to everyone, it really deerves... :]

**** [Jun 17, 2001] by me
I tried a number of security apps... I wanted someting that would be easy enough that I'd actually use. Gridlock was the easiest and most reliable non-preinstalled app. It's easy to use.... easy to re-assign passwords to... and allows a time-delay option, so I can turn the comp on and off for a few minutes without having to unlock the comp.

***** [Jun 1, 2001] by Løck
Great Software! Genial, simple, powerful and fast! :] Compliments to the author.
I'm still trying it on the emulator at office so I don't know if the (small) problem I found it's real or not. I enabled GridLock and the internal Palm password. Then turned it off and on. At this point I have to insert 2 times the code... Maybe it's emulator? Another thing is the "active keys". I turn on the emulator and I have the grid. If instead to insert my code I press hard keys, after accessing I found that Palm is in the key-application. In short words, let's say I turn off Palm while I'm in phone numbers. I turn it on and I press TO DO. Then tap the code and I find myself in TO DO. If this is emulator, please forgive me, if not, it may be a suggestion for next versions. Compliments again :]

***** [Apr 1, 2001] by C. Joseph Drayton
I have to say that this program is excellent. It allows you to lock your PalmOS machine with confidence. More importantly, you can unlock it QUICKLY for access. It is so fast, that I have it lock the minute I turn it off.
The only thing that could make it better is if it ran from flash so that I could use it under JackSafe to survive a hard reset. Add this feature and I will gladly pay 19.95 to register it!!!!

***** [Mar 31, 2001] by Rock Roberge
I have a need for Palm security, but I never liked having to enter a password when powering on my Visor. Gridlock is an Outstanding (and FREE) solution. Thank you very much for writing this quality application and making it available for free, I really love it.

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