A Word of Warning About the VisionAssist App

Member of the AppleVis Editorial Team

A quick word of caution about an app that's just been released called VisionAssist.

The app has been developed specifically for those with low-vision, and claims to offer the same functionality and  performance that you would expect from a handheld electronic magnifier, but with a few extra features and the advantages of being on your phone.

I had high hopes for this app, so was very disappointed to find that it was totally unusable on my iPhone 4. Or at least it is unusable if you need to be running VoiceOver at the same time.

For those of you who have tried using the latest version of Navigon on anything other than an iPhone 4S, picture the erratic and unresponsive behaviour that you experience from VoiceOver, and then multiply that by 5.

It looks like the video capture on VisionAssist is a major resource-hog, and as a result there aren't enough resources left for VoiceOver. This means that VoiceOver becomes horrendously erratic and unresponsive. It is impossible to reliably navigate page elements. VoiceOver focus randomly jumps from one page element to another, and when focus is on an element it is almost impossible to action a gesture (such as double-tapping on a button). Just once I was able to get the pause button to work by using a split-tap. When the video was paused, VoiceOver became more responsive, and I was able to use some of the controls (such as going to the settings page). Despite many attempts, I have not been able to activate the pause control again.

The only way to get my iPhone back working properly was to kill VisionAssist via the App Switcher.

This lack of responsiveness from VoiceOver when using VisionAssist seemed to be a lot worse than what I have seen with Navigon. With some patience and use of the split-tap, I am still able to use Navigon. This is not true of VisionAssist. The app was unusable, and it made the iPhone pretty much the same until the app was killed.

Based upon my experience, I would suggest that anybody with an older device avoid this app for now. I am in contact with the developer, and hopefully he will be able to address this problem.

I do not know if this problem would be present on the more powerful iPhone 4S. I do have a promo code for the app, so if a 4S owner would like to test and report back, please contact me.

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Promo code now gone

Member of the AppleVis Editorial Team

The promo code has now been passed to somebody with a 4S, so we should find out soon whether the extra power of the 4S makes the app usable.

Problem confirmed

Member of the AppleVis Editorial Team

It's now been confirmed that this app is currently not usable on any iDevice if VoiceOver is enabled. This includes the 4S. For now the developer has added a note to the app's description that it is not compatible with VoiceOver, and is working on a solution that will allow the app to work with VoiceOver without degrading the performance of the app.

4S Confirmation

I was the one who received the promo code and tried the app with the 4S. I can indeed confirm that the Vision Assist app isn't yet compatible with VoiceOver. Here's a few thoughts on the app overall. I think this app has great potential for being a comperable video magnifier. One feature that is usually lacking in other magnifier apps is the color contrast modes. Many people find it easier to read with a black background and white text, or other color combination. I also like the grayscale mode. The freeze feature is also good. One thing that would be nice to include here is a button to save a frozen image to the pictures area of the device. Maybe just have a Save Picture button in the corner when an image is frozen on the screen. Visually, there are a couple of improvements I'd like to see. I'm not sure how much can be done with the limited access to the camera hardware though. When in full color mode, the image is pretty clear, and text can be read at a good speed. when switching to a high contrast mode however, the image tends to blur a lot more, so it's necessary to move the phone a lot slower across the page. This may be due to the camera refresh rate or other specs. I notice this on other dedicated portable video magnifiers from time to time. As for VoiceOver performance, here is my experience. I can move my finger around the screen, and with quite a bit of lag, can find most controls consistently. Oddly enough, I can't interact with them. when tapping the settings button for instance, nothing happens. Turning VoiceOver off makes everything work fine. I didn't have the same performance issues when minimizing the app. I can leave the app open on the 4S and my phone still runs fine. I just get the major performance hit when the app is actually active. I did notice that the Mode button and the Flash button are labeled the same thing. voiceOver speaks Mode Button for both controls. The Help button is also not fully labeled, but it's easy to understand it's label as help. I believe VoiceOver just says the image name. Once the performance issues have been resolved, Vision Assist may be a great magnification app for visually impaired users. I look forward to future updates to this app.


Member of the AppleVis Editorial Team

Jesse, thanks for sharing your experiences and observations. Like you, I think this could be a really useful app once we can get it working with VoiceOver. I believe the developer has already corrected the button labelling for the next release. Hopefully he will look at some of your other suggestions too.


App Developer

Hi Jesse and David, Thanks for both of your constructive feedback - this is very useful feedback which I appreciate. FYI - Saving picture is on the list for V2. I will share what I talked about with David by email. --- I have now reviewed the VoiceOver implementation, I have improved the labelling of all controls and components. On your website you use the term resource-hog, which is true :-), as it was intended to use as much performance of the device as possible for its image processing routines to give the best framerate. Unfortunately, this seems to now be conflicting with VoiceOver. I am currently working through a couple of techniques to limit the framerate and enable VoiceOver to work acceptably. From a technical perspective, most of the image processing is done on the GPU which should be keeping the CPU free for multitasking. I wonder if Apple are also using the GPU for VoiceOver? As an aside - I test VisionAssist on the iPhone 3GS, iPhone 4S, iPod Touch 4G, and iPad 2. All these devices give pretty good performance without VoiceOver on. I will let you know once I have resolved the VoiceOver issues. In the meantime I have noted that VoiceOver is not supported on the website and AppStore. Thanks and stay in touch.

Thanks and Camera Question

Thanks for the update. I'm glad to hear things are going well. I look forward to seeing future app updates. I do have one other question I forgot to write in my last post. I've wondered this about other camera apps as well. Does the iPhone camera allow for, or can some type of image stabilization be enabled for apps? This would be especially useful in a magnification ap when zoomed in. the more you zoom in, the more jittery things become. I'm just curious if the current IOS devices support this type of thing.

Image stabilisation

App Developer

Hi Jesse, as of iOS5 there is no Apple provided means of image stabilisation. I agree, at higher zoom levels it becomes very difficult to hold steady - and this is why I see users freezing (pausing) an image and then zooming in. It is also why I have limited zoom to 5x, as I do not see a lot of benefit in greater magnification. Perhaps next week Apple may announce some additional capabilities with their iPad 3? fingers crossed! Regards Mike

Improvements on the way

Member of the AppleVis Editorial Team

I've just tested a beta version of this app that contains fixes for the problems mentioned above, and it works very nicely with VoiceOver. I've only the briefest of experience of using a handheld video magnifier, so cannot comment on how the performance and usability of this app compares. However, as somebody who has enough residual vision to get lots of use from this kind of app, I can see it fighting for a place on my iPhone's dock. Because of the nature of my eye condition, a high contrast (white on black) option is almost essential to make any magnifier truly useful. The only other magnifier app that I have used that offers this feature is ZoomReader, and my experience was that video performance degraded so much in this setting that it was virtually unusable. This is not the case with VisionAssist. Hopefully the updated version will be in the App Store shortly.