UPDATE (21 January 2026): Flip Unit is now live on the App Store: https://apps.apple.com/app/id6757921823
TestFlight remains available for testing upcoming features.
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Hi everyone,
I'm a developer who has built a free unit converter app called Flip Unit with accessibility as a core priority, not an afterthought. I'd really appreciate feedback from VoiceOver users to make sure I've done it right before the public launch.
The app includes:
- 6 conversion categories: Cooking, Currency, Distance, Temperature, Weight, and Area
- Full VoiceOver support with clear labels and announcements
- Dynamic Type support (all text sizes)
- High contrast mode
- 162+ live currencies
- Smart cooking conversions (ingredient-specific, like cups of flour to grams)
This is a passion project and will remain free forever - no ads, no tracking, no in-app purchases, no premium tiers, no data collection. I built this because most unit converters have poor accessibility, and I wanted to create something that works for everyone.
Note: This is volunteer testing for a free app - no paid compensation is offered.
If you're willing to help test, you can join via TestFlight here:
https://testflight.apple.com/join/aKjUEWfG
You can also learn more about the app at https://flipunit.app
I'd especially love feedback on:
- Whether VoiceOver navigation makes sense
- If any labels are unclear or confusing
- Any issues with the unit picker/selection screens
Thank you for any help you can offer.
Siraj
Comments
Seems very reliable and great for first look
I haven’t necessarily tried all the conversion units, but I did try the temperature and distance units, and they’re looking very good.
One thing I’d like to see is this: when selecting the conversion units, clicking the button to open the dropdown list can remain the same, but would it also be possible to add the conversion units as VoiceOver actions so we can reach them just by swiping up or down for quick access? Another option could be to make conversion units appear via swipe up or down only if we set them as favorites, so we would only see our favorite or most frequently used units. It’s a great app, thanks so much for the work.
Mert Ozer -Thank you so much for testing and for the kind words!
That's a really helpful suggestion about VoiceOver actions. I hadn't considered adding swipe up/down to cycle through units directly - that would definitely be faster than opening the picker each time.
I'll look into implementing this, perhaps with the most frequently used or favourite units as you suggested. It's exactly the kind of feedback I was hoping for.
Thanks again for taking the time to test and share your thoughts!
Siraj
A couple of suggestions.
Hi, Siraj.
A very nice app. Very well laid out. I want to make a couple of points. In the temperature conversion section, I could not use zero as a value even though zero is a valid temperature. Also, I did not find a way to insert negative values since I couldn’t find the minus sign in that keyboard layout. Great work! I can see myself using this app quite a bit.
@Theepan
Hi Theepan,
Thank you so much for the kind words and for catching these issues - I'm a bit embarrassed I missed something so obvious! Zero and negative values are essential for temperature conversions.
I'll get both fixed in the next update. Really appreciate you taking the time to test so thoroughly.
Siraj
Improvement suggestions
Thanks so much! I completely agree with the previous comment that for any category both in the from as well as to fields, we should be able to flick up or down (voiceover gestures of course is all I’m talking about here on my comment), to flick through all the unit choices of the different standards such as metric and imperial. it’s all about efficiency and speed given that screen reader usage anyway typically takes longer for a blind person than a side person so whatever an app design can do to expedite the process requiring fewer swipes and double taps etc. is always the best. secondly, after I have chosen the number in the number that it failed, and chosen the from as well as to fields, currently the done button which must be pressed is all the way man the user on the done button? totally, there is a fixed hip on the app screen that says “swipe left on any category to add it to ferrets“. This doesn’t seem to be a tip for voiceover users. It may be just four sided people and if that’s the case then that tip is not only vomiting all your screen users but it also does not work using voiceover. to the text of the tip mention above should be removed and another implementation to add a category to favorites that is voiceover friendly should be included. ideally it would be unified for both sided and blind people so after removing that text of the tip I mentioned, maybe one has to enter a category and then there can be a button write the beginning before you start adding that number and filling out the fields that would say add to ferrets and once it’s added to a favorite that button label should automatically switch to “remove from favorites”.y swipes later at the end of all the tabs at the bottom. Can we move this done button to appear right after the to field so that a single right swipe from the TO
ChatGPT versus flip unit
First of all I totally want to acknowledge that such apps as the flip unit are super helpful for screen reader iOS users who do not use AI apps or have low proficiency in prompt engineering and effective use of those AI apps. Personally I am a ChatGPT subscriber for more than a year and a half now and I just using its inbuilt shortcut opened up the advanced voice mode which is in my iPhone home screen dock, and GPT really really quickly converted any unit to any other unit that I asked you to. Since this was all in voice mode and no text typing even required, it required like a fraction, literally a fraction of the swipes and double taps compared to the flip unit app to achieve my conversion goal. So personally I will be using the single convergent ChatGPT app for any of my unit conversions instead of having five different apps on my phone each doing a different thing for example. So please pardon me, but personally I don’t have a motivation to do further testing on the flip unit app. However to re-trade and circle back, I truly appreciate this app and his refinement because there are many blind screen reading iOS users cool for one reason or the other don’t use AI or have AI apps but don’t know how to use them effectively which is fine, and for them such separate dedicatedunit conversion apps would be very useful.
Good update and another suggestion
I got the update and zero and negative values work in temperature now. Thanks! I have another suggestion. It would be nice to be able to favorite unit pairs instead of or in addition to the categories. Basically, the ability to add Celsius to Fahrenheit. And Canadian dollar to US dollar as favorites for example.
Since we use some conversions more than others frequently.
@ Prateek Dujari
Hi Prateek,
Thank you so much for the detailed feedback - this is incredibly helpful.
Swipe up/down for units - This has been requested by others too and is definitely on my list for a future update. I agree it would make navigation much faster.
I really appreciate your honesty about ChatGPT being your preferred tool - that's completely understandable. As you said, this app is aimed at users who prefer a dedicated, simple tool without needing AI proficiency.
Thank you for taking the time to test and share such thoughtful feedback. It will genuinely help make the app better for the VoiceOver community.
Siraj
@Theepan
Hi Theepan,
Thanks for confirming the fix works, and for continuing to test and share feedback!
That's a thoughtful suggestion about favourite unit pairs. To keep the UX simple and minimal, I'm considering an alternative approach - saving the last used units for each category. So when you return to Temperature, it would already have Celsius to Fahrenheit pre-selected from your previous conversion. Same for Currency with your Canadian to US dollar pair.
This way you get the convenience of quick access to your frequent conversions without adding extra UI complexity.
Thanks again for all your help testing - really appreciate it.
Siraj
Website is Very Helpful...
I haven't yet started testing your app but would very much like to do so. I've already got TestFlight on my phone and will click the link. I wanted to say that your website is very accessible and helpful. An app such as this would be a great help for me.
Re: Flip Unit
What does this app do that the native iOS Calculator does not? Thanks in advance for your time. :)
@FmNgqRZd
Hi,
Great question! You're right that the native iOS Calculator now includes unit conversions since iOS 18 - it covers a lot of ground with currencies and measurements.
What Flip Unit offers differently:
- Results are announced automatically by VoiceOver, rather than having to tap on the result to hear it
- Ingredient-specific cooking conversions (e.g., a cup of flour weighs differently to a cup of sugar)
- A configurable history section that's easier to navigate
- A simpler, focused interface just for conversions
The app will also be updated with more features based on feedback from this community - for example, VoiceOver actions on unit selection is already on my list thanks to suggestions here. One advantage of a small independent app is that this community can directly shape how it evolves, which is harder to do with Apple's built-in apps.
That said, if the native Calculator works well for you, that's perfectly fine! I built this mainly because I found most converter apps had poor accessibility, and I wanted something that worked seamlessly with VoiceOver.
Siraj
@Ekaj
Hi Ekaj,
Thank you so much - really glad to hear the website is accessible and helpful! That was important to me to get right.
Looking forward to your feedback once you've had a chance to test the app. Don't hesitate to share any thoughts or suggestions here.
Siraj
Feedback
Hi Siraj.
Thanks so much for creating and sharing this app; it's a very nice little utility to have on the phone. I just have a few thoughts.
1. It'd be nice if Favourites and All Categories on the main screen were tagged as headings. It'd just make VoiceOver navigation a little easier and would more clearly separate content sections.
2. If I add Distance for example to Favourites, its VoiceOver label changes from "Distance, button" to "Distance, Favourite, button". I find this additional verbosity a little annoying, and it's unnecessary as I already know it's in the Favourites section.
3. For Cooking, it looks like it is using the American standard for a cup measure. I wonder could an option be added in the settings to choose between American, Modern Metric aka (European or International), and perhaps even the old Imperial cup measures?
4. This one might be more of a stretch, but perhaps you could create controls that can be added to the Control Centre that would jump you straight to Cooking or Distance etc.
Thanks again, appreciate the app.
Dave
@Dave Nason
Hi Dave,
Thank you so much for the detailed feedback - this is exactly the kind of thoughtful input that helps make the app better.
On your points:
1. Headings for Favourites and All Categories - Great suggestion. I'll add proper heading tags to improve VoiceOver navigation in the next release.
2. Redundant "Favourite" label - You're right, that's unnecessary verbosity. I'll remove it in the next release.
3. Cup measure standards - Good point. Rather than adding settings complexity, I'll add the different cup measures (American, Metric, Imperial) as separate units so you can pick whichever you need.
4. Control Centre shortcuts - Interesting idea! I'll add this to the roadmap for a future release.
Really appreciate you taking the time to test and share such specific feedback.
Siraj
compensation rate
Sounds like a nice little app? What rate are you offering for Voiceover testers?
Excellent
I don’t really have a lot to say but for feedback and an initial review, it’s very good. I’ve always wanted to get an app that you can convert from one measurement to another so thank you very much.
@Brass
Hi Brass,
That's a fair question - I should have been clearer in my original post. This is volunteer testing and no paid compensation is offered.
I've updated the original post to make this clear. Thanks for pointing it out.
Siraj
@Saj
Hi Saj,
Thank you for testing and for the kind words - really glad it's useful for you!
Siraj
Quick update — Flip Unit is now live on the App Store!
Flip Unit App Store Link:
https://apps.apple.com/app/id6757921823
Thank you to everyone who tested and gave feedback. Your input genuinely shaped this app.
I'll continue to push new features to TestFlight first for testing, then to the App Store. The VoiceOver actions and 'remember last unit used setting' that several of you requested is on the roadmap.
Siraj