Category Archives: iOS

[iOS] TravelCalc iPad crash problem has been resolved in V1.1.1

After some efforts on code change, the crash problem of TravelCalc V1.1 on iPad has been resolved. Apple has approved the submission of patched version to app store in short time (Thanks to Apple reviewers). Now users can download this version to fix the problem.

The root cause of this problem is code fragments added for support to “Dark Mode”. To control the change of “Dark Mode” and “Light Mode” colors, I have to find some place in application initialization to insert related control flows.

However, when iPad executed these code fragments, something just went wrong in initialization process. A component of calculator will encounter problems and fail to pass the initialization.

After this patch, the problem has been fixed. I just suggest all iPad users to upgrade to this version, V1.1.1. iPhone users could use V1.1 as well, but still recommend to upgrade to use V1.1.1.

Meanwhile, V1.1.1 also added two new options to control TAX/TIP cyclic calculation and tax refund calculation formula. Users could get more flexibility for TAX/TIP calculation with version 1.1.1.

Sorry again for any inconvenience that may cause of V1.1 update. I’ll take more care on code fragments change with future updates.

Still during this world-wide pandemic, may the HEALTH be with you. Keep healthy until we could travel around the world again!


[Urgent] iOS TravelCalc V1.1 on iPad may encounter Crash in Landscape mode

Photo by Seb Mooze on Unsplash

The iOS TravelCalc has had an update with version V1.1 recently. I’ll prepare another article to describe the details about this update. Today I’d like to focus on the crash problem of this version on iPad in landscape mode.

What happened?

From the analysis data been received by now, there has been over 20 users affected by this issue. The symptom is crash after launch of TravelCalc on iPad under landscape mode. This issue will affect all iPads with iOS 13.0 and up.

The root cause of this issue is some code fragments changed for supporting “Dark Mode” after iOS 13. When use change the appearance mode, TravelCalc should change its own display mode and set the correct color code to each related component. To accomplish this, some new code fragments should be added to a rarely used event location. Under landscape mode of iPad, this action will make a component in TravelCalc disappear and appear again after the change of appearance mode . During this period any attempt to co-work with this component will lead to CRASH.

How to resolve it?

To solve this issue, an updated version of TravelCalc with version number V1.1.1 will be submitted to Apple for review. Once approved, users will be able to update to this version and cease this problem. The planned schedule for this patch will be within this week, before 6/20, 2020.

There is a workaround of this issue before the patched version. You may set iPad in “Portrait Mode” before launching TravelCalc. The App will lock the direction of screen into Portrait Mode after successful launch.

Final words

Sorry for any inconvenience that may cause to iPad users. The patch is on the way. I’ll send it to Apple for review once the package is ready.

May peace and all blessings be with you during this worldwide pandemic.

iOS TravelCalc, customized rates exchange calculator:

iOS Travel Calculator now available

After some days waiting, the iOS version of Travel Calculator is now available to download on App Store.


This App can help a lot while performing overseas travel. Especially when you need to exchange foreign currencies you will find it be very useful.

OFF percent button with customized percentage gives you one touch to get discounted price/values. TAX/TIP button will release your valuable time while traveling.

And, the most important of all, you can customize your own currency rates. You may encounter such condition. You just exchange some foreign currencies with some specific rate. But the rate is changing everyday. When you press update button, you don’t want to change the target currency rate to the up-to-date one. In the opposite, you just want to keep it and lock it down. With Travel Calc, you can do this easily.

Click settings and select “My Rates”. Input your own rates and click on “Lock this Rate”. No more update will be applied to your rates. You can then take this rate to the target country and get real expenses in your own currency.

Hope this App could help a lot of people for the currency exchange works.

Travel should be wonderful and happy. As to currency, TravelCalc just makes it easy!
Download Travel Calculator iOS on App Store : Here is the link!