You've made an app for Android, iOS, Windows - what about the user interface?

It's all bollox while the number of different form factors and screen resolutions vary so much; yeah, the coding might be easier with a framework, but the user testing is still a bastard (even if everything comes back junky dory, it's still an expensive, time consuming business).

Of the two main platforms, Apple appear to suggest/require the most adherence to a particular UI design standard...this can be good and bad in equal measures.

It's best to target each UI

People know how to use the UI on their chosen phone and resent having to learn "a new way". Also you have to code for differences between platforms- a good example would be a lack of a menu button on iDevices means you need to display a constant tabbar whereas the screen real-estate can be reclaimed by Android because there is no need to display the extra items until the button is pressed.

As the old saying goes: Horses for courses...

Don't be lazy. Develop a proper UI for each phone or just do something else like flower arranging.

A cheap crappy app that both iOS and Android users will hate does your company image no good at all.

Lowest common denominator

Sadly for the author of the article, the use of "lowest common denominator" in popular culture to refer to "the most basic, least sophisticated level of taste, sensibility, or opinion among a group of people" is older than he is, since it dates back to the early years of the 20th Century. The use in cross-platform UI work (the use discussed in the article) refers back to this meaning, not the mathematical one, and encapsulates the idea of a minimal set of features that work everywhere. The goal of building the maximal set of features that work everywhere is a noble one, but fraught with complexities and testing issues.

The actual valid maximal set of features will change from revision to revision of each target platform, and is therefore not something that sane organisations would target. Example: IOS 6 changed something in text-box handling, which broke a translation-dictionary app I have on my iPhone. It was evident that the problem was fixable in the app, because shortly afterward, the publisher released an update that addressed the problem. My best guess is that some app-level behaviour that was outside the strict spec of the control, but tolerated or accidentally functional, became outside the actual behaviour expected by the implemented control. This sort of thing makes the "highest common intersection" something to be avoided. Instead you develop for the smallest set of common UI functionality that is useful for your application / framework.

It's a delicate dance, since the "lowest common denominator" has to be tempered by the insertion of the word "useful", or you are likely to be left with a UI that consists entirely of simple pushbuttons.

Nothing worse than an Android app that inherits all the iPhone design failures

like the menu button all the way up on the top left of the screen #fail.

Yes, BBC, First DIrect and others, looking at your piss-poor excuses for Android apps.

Silver Bullet syndrome

Trying to avoid coding for each independant OS is like believing that Silver Bullets truly exist.

Laziness is rarely good..

..but going out your way to theme an app. on Android to clone the iOS experience is criminal. Recently tried looking for a bird watching App(not for me honest :) and found a gem. It just didn't work for me as iOS is just alien (although could be it was just a crap App). Any cross platform that does not go native at the user level is poop.

My money is on HTML 5 based apps with API for hardware in the long run.

What about wxWidgets and QT?

These both supposedly are cross-platform, allowing for development on one OS platform and deployment to multiple others, with minimal rejiggering after compile time (maybe even before compile time)...

Check out some samples of just wxWidgets:

http://www.wxwidgets.org/about/users.htm

http://www.wxwidgets.org/about/screensh.htm

http://www.wxwidgets.org/about/feature2.htm

There are some really kewl apps out there in wxWidgets. Makes me wish I could understand the tools so I could at LEAST prototype some things, namely build my own database app that mimics or lets me recreate Lotus Approach (while trying to dodge patent litigation....). Actually, I wish somebody ELSE would mimic Approach, and stop mimicing Access. Not saying kill Access. Just saying I wish SOMEbody would help of Approach users have a modern, Open Source version of Approach but one that can handle italics, unicode, and give it horizontal sliders on detail tables that are wide with data, and enable embedding chart elements on repeating panels/detail tables, and endow the cross tabs with more features. So far, all the other open source database efforts do nothing to unseat me from Approach. Now that WINE hit 1.4x, Approach, WordPro, and 1-2-3 seem (so far) to be working find. Even Flywheel works, and that enables me to make the SmartSuite apps respond to the mouse scrolling.

And, yes, I did try to run wxWidgets and QT, to try to make a database app. I could not find the components for database connectivity. They used to exist back yarens.. Umm, years ago. I must not have installed them. So little time, so much frustration when clueless like me cannot even make our own apps

Look at StoryLines. That's a brilliant piece of software for writers and screenplay authors. Other apps are out there, too, and wxWidgets works on/targets more than just PCs... (Disclaimer: I do not have any dealings nor relations with the developers or maintainers of wxWidgets, other than that I twice bought/upgraded StoryLines. It's so kewl I just had to have it, though, sadly I have not produced anything storywise yet...)