Tag Archive: protractor

Sorry we’ve been busy with other things so we haven’t got a chance to update the apps for quite a while. It turned the new Android versions don’t work with some of our old code very well. It causes some serious freeze issues on most of our apps (ruler, level, protractor etc.) We found out what’s going on and released a new versions for all those apps. As far as I can tell, all apps should work fine now on most of the phones. So sorry for the late updates.

There were a lot of complaints about the  Advanced Tally Counter where the name of the counter is not showing. The root reason was discovered and a new update was posted for both the free and the paid version.

Advanced Protractor Pro 

Last but not the least, we updated the Advanced Protractor Pro to include a neat feature – to help Photographer to find out what lens to bring for a particular location. Well, it sounds like nothing to do with a protractor when you first hear this. But here is how it works.

What lens to bring is a question that all photographers will ask themselves before going out for a photography trip. Sometimes it is a tough question. Bringing them all is an easy answer but not an easy decision for a strenuous hiking. This Advanced Protractor Pro will help you to scout the location beforehand and help you making the decision.

Last winter, I went to the famous Horseshoe Bend near Page, AZ. My first question, before I went there, was what kind of wide angle lens I would need in order to capture the whole bend and the side cliffs. I went to the Google Map for help. If  I have a real protractor, I can put it on screen to find out the angle of the span, then use an online angle to focal length converter, I can figure out the lens focal length. But isn’t our Advanced Protractor Pro is a better protractor? This triggers me to add this new feature.

First, you go to settings to change the display of the angle degree to focal length.


Next, long press and hold the multi-function round button so that you can see three green circles on the screen. Now press Menu – Toggle Camera to turn on the camera.

The next step is to use your computer to open the Google map to navigate to the place you are interested in. Use the app camera to take a picture of it. (Yes, we plan to release another app to show the Google map right in the phone but here is what you have to do with the app right now)

Now you can drag the handles on the screen. Put the center one at where you will stand when taking the photo. The other two handles at the widest angle that your photo will cover. In this case below, I will stand at the rim of the cliff to capture both walls. The focal length calculated by the app is about 18 mm (or 12mm if taking picture vertically). Note that this is the focal length for a full frame sensor in the landscape mode. If you have a crop sensor, you need to divide it by 1.5 or 1.6 whatever the crop ratio is. You also need to adjust it if you plan to capture in the portrait mode.


Is it for real? Yes of course. Here is a picture I took last Winter when I was there. As you can see from the EXIF information, I used 17-40 lens at 19 mm.

Horseshoe Bend

Here is another one. If you want to capture both the Half Dome and the two falls (Vernal fall and Nevada fall) from the Glacier Point, you would need about a 32mm lens or 21 if vertically. If the cloud is interesting, you probably will take the picture vertically thus a wide angle lens such as 17-40 or 14-24 is certainly required.


How about the Bellagio music fountain? To capture the whole fountain needs a really wide angle lens, probably a fish-eye. But a nice composition is to capture both the Bellagio and the Caesars Palace hotel buildings as background and use the fountain as foreground. The app tells me it is 19 mm.


I actually use a 17 TSE so that I can more room to crop and also be able to shift the lens to get rid of the distortion for the high buildings.

7-11-2013 1-28-30 PM

Obviously, I hijacked the Protractor Pro to squeeze in this extra feature. I only spent an hour or two to add it. It is clearly not enough. The next app we will do is to create an app for Photographer do something like it but it will do more. Please stay tune.


We just post updates to Advanced Ruler (Pro), Advanced Protractor (Pro) and Advanced Bubble Level (Pro) to fix the compatible issues with Android 1.5 and 1.6. Please give them a try if you are on those firmware versions.

[Developer’s talk]

We used to support all levels but in the last update to fix the camera preview issue on Galaxy S, we broke the compatible because we used a Android 2.1 only method. Because of that, Android 1.5 and 1.6 users would get a force close with a VerifyClass error. In a regular Java program, we just need to add a “if” statement to check the version first and only call the Android 2.1 only method if the Android version is 2.1 and later. However on Android, this workaround doesn’t work. As long as a class uses a new method, no matter it is triggered during runtime or not, a VerifyClass error will be thrown when VM tries to load it. So we end up using reflection to call the method. Not fun at all. I also noticed some publishers post different apk files for Android 1.5. This doesn’t sound like a good solution as it will force users to purchase it again when he/she upgrades its phone’s firmware. If Android market support several apk files for the same app on different Android version, it would be a useful feature.

Anyway, the good news is more and more users are moving to 2.1 and 2.2. I just found the following updates on Android developer website. Only 17% people are still on Android 1.5 and 1.6 which is considered as “old” version. The data is collected during two weeks end on December 1, 2010. No wonder no that many people complained about the compatible issues on our apps.

Platform API Level Distribution
Android 1.5 3 6.3%
Android 1.6 4 10.6%
Android 2.1 7 39.6%
Android 2.2 8 43.4%

Here is the historical distribution.

[Source: http://developer.android.com/resources/dashboard/platform-versions.html]

Post updates for all the tools

I just post updates to pretty much all the Advanced tools apps on Android market. The main fixes are
1. Fixed camera preview not working on Samsung Galaxy S phones. It affected Advanced Bubble Level Pro, Advanced Ruler Pro, Advanced Protractor Pro
2. Added market licensing checking to all paid apps
3. Use ProGuard to obfuscate all the apks to protect our copyright
4. Made no sounds by default in several apps as people complained the sounds are annoying.
5. Phone database updates for Ruler and Ruler Pro


Several users suggest we should add camera feature to Advanced Protractor we released a few days ago and make it a paid app. So we did. It is actually quite neat. You can start the camera preview feature and the camera image will show up to cover the whole screen and the protractor is shown as an overlay on top of it. All you need to do is to align the protractor origin with the angle’s vertex and freeze the image. Then you can use finger or keypad to adjust the protractor hands to line up with the vertex’s edges. In the Pro version, we added a second protractor hand so that you use both protractor hands to measure an angle.

In order to get an accurate measurement, here are some key points.

  1. Always enable the second protractor hand from the settings when using camera. It is enabled by default in Pro version. If you don’t use the second hand, it is difficult to line up the origin point and one edge at the same time when you try to freeze the image.
  2. Make sure your phone is parallel to the angle you want to measure
  3. Use keypad to adjust the protractor hands, of course, only if your phone has a physical keyboard. They left/up and right/down keys will adjust the hand by -1 and 1 degree respectively. Shift+arrow key will adjust by 0.1 degree. By default, the first hand will be adjusted. If you hold Alt key at the same time, it will adjust the second hand. When you try to line up the edges, keypad will be a lot easier to use than the finger dragging.

I haven’t seen a protractor on Android market. After we did the Advanced Ruler, we decided to make a protractor to make our offer complete.

Even though we called it Advanced Protractor, it is both a protractor and a level/plumb. It works in both auto mode and manual mode. In auto mode, the protractor’s hand will move with the phone orientation. In this mode, it can be used as a level/plumb. We read the values from phone’s sensor so I guess the accuracy depends on those sensors. We can’t guarantee the accuracy but when we tried on Droid, it is quite accurate. In manual mode, the protractor’s hand will move with your finger. You can use it to measure angle on paper like a traditional protractor.

Here are the list of features.

  1. Auto mode: can be used as level/plumb and protractor, manual mode: works like a traditional protractor
  2. Different background. Swipe left and right will change the background instead of going through settings screen.
  3. Multi-function phone to toggle measure mode and the protractor hand position
  4. Lock button to lock the reading so that you have a chance to write the value down