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Testing and Issues

You can test this app and submit issues during the testing period of the iOS Chart contest.

Install .ipa files via AltStore

Entries with serious issues will not be able to win the contest, but even minor issues might be important for overall results.


by rating


Good speed, but graph lines exceed the maximum graph height in charts #1 and #2. This is considered critical.
iPhone 6 Plus, iOS 12.1
Young Deer Apr 28, 2019 at 11:13
Interesting, thanks.

Upd. Issue was in scale calculation on iPhone+. There scaling around 2.6, not 3.0 that gives UIScreen.main.scale. Now calculation uses drawingSize property.
Sergey Dikovitsky Apr 17, 2019 at 17:52
It's possible to hide line on the chart where it should not be possible. At the same time user can see yellow circle in this state.
iPhone 5s / iOS 12.2
Young Deer Apr 17, 2019 at 18:11
Oh, thanks! You'r good tester)
Sergey Dikovitsky Apr 17, 2019 at 17:50
Minor issues related to design: insets for buttons, range selection, chart and y-axis lines do not match. View for values has incorrect design too: titles not aligned, value and % symbol have spacing. Arrow looks incorrect. Small chart on background of range selection control has top inset.
iPhone 5s / iOS 12.2
Design issues:

1. Dates on the right edge overlap
2. Percentage mini chart doesnt use 100% height
3. theme change button is at the bottom
4. single bar chart shows "all" row and overlaps the cell header
5. percentage tooltip has red indicator
6. Putting tooltip and scaling can remove the tooltip but leave the line with circles (see video)
Issues with landscape mode:
1. buttons overlap
2. charts have dates clipped
3a. second chart right axis labels are in the center
3b. upon return to portrait right axis labels are invisible
iphone6 12.1.4
Fair Quokka Apr 27, 2019 at 20:24
— The third graph blinks when filtering.
— The graph preview is incorrect.
— Points for filtered data don't disappear from the graphs (the attached screenshot).
— The 'Night Mode' button is at the very bottom of the page.
— The headers are missing.
iPhone 5s, iOS 12.1
Crash on start
iPhone 5, iOS 10.3
Young Deer Apr 25, 2019 at 18:49
Your device must support metal.
Sergey Dikovitsky Apr 17, 2019 at 17:51
Sum of values gives 99%.
iPhone 5s / iOS 12.2
Young Deer Apr 17, 2019 at 18:09
Not sure how to properly display percents if we have 38,3. I round it to closest. So as result we have 99%
Hard 2Y animations. But application is very fast works :)
iPhone 5s, ios 11
1. Charts indent is too big
2. axis lines have 100% screen width
3. applying filters on second chart doesnt hide respective axis labels
4. Navigation bar not by design
5. Applying filters on line chart doesnt remove the circles for the tooltip

basically only ui issues, but many
iphone6 12.1.4
Deleted Account Apr 20, 2019 at 11:13
Selection info is drawn under the grid labels.
Deleted Account Apr 20, 2019 at 11:22
Bars can stay overlapped with the chart header.
Does not support iOS 8. Telegram does.
Young Deer Apr 25, 2019 at 18:52
Telegram are good)
maxY on chart has to be on the same position as y-coordinate of the highest y-value by design
Young Deer Apr 25, 2019 at 18:57
For me it will looks strange to see labels 751, 654 .. etc. For you expected behavior you need just comment one line.
Major issue: filter toggle doesn't not affect y-scaling
values are clipped
After some actions this horizontal separator above the slider shows up. And every time I try to catch it with internal video recording or screenshot, it disappears! Looks like this artefact is related to common work of MTKView and CALayers.
iPhone 6+, iOS 11.2
Landscape transition is really bad. I think it is because this app uses Metal.
Critical issue: Poor line quality. It is visible even without zoom. It is not easy to implement good line quality on bare Metal, MSAA is not enough. Qualitative line drawing requires a lot more calculations and tricks. And such implementations may still be worse than Core Animation / Core Graphics quality and would definitely affect the performance. You can read more about line quality in Metal projects in my comments on entry228.
iPhone 5S, iOS 12.2
Young Deer Apr 25, 2019 at 19:01
Seams you have microscope. I didn't see any problems, so I not use addition triangles with alpha for antialiasing.
Critical issue: Line joints are not rounded, even on iPhone X. So, it's not some minor optimization for old devices, rounded joints implementation on Metal require a lot more math to implement, a lot more vertices to calculate for each frame and 2-3 times more polygons to draw.
Young Deer Apr 25, 2019 at 19:05
Yes. There is lot of things to improve. I thing about adding one more vertices to make joint more round(or 2 if one is not enough). If we have infinity amount of time, I will implement it too.
Critical issue: This code uses Metal and it will never work on 32-bit devices (including iPhone 5 on iOS 10.3).
Young Deer Apr 25, 2019 at 19:10
Why is critical? Nowhere it's written about. It must work on iOS 12, so iPhone 5 is no there. Why is Metal? Cause it's not real work, it interesting to experiment? see performance of metal and dig inside how GPU is works.
Major issue: It's not so easy to port this code to iOS 8 on iPhone 5S either, because he uses help classes from MetalKit (otherwise he would support iOS 8). And you have to do a lot more work without it.
Young Deer Apr 25, 2019 at 19:17
Oh, man.. your review is awful. If you show yours app in store, I can generate thousand issues like yours. Seriously. Do all yours app support iOS 8, maybe iOS 7? Several days ago I fix some bugs in app with iOS 7 support. It still works. Don't be poisonous.
if you drag right side of the slider, you can affect left side too!
Young Deer Apr 25, 2019 at 19:18
Is it issue? Maybe feature?
Nobody added any issues yet...