Adopting sidebars in iOS apps

Question

It looks like several known apps for iOS (Foursquare, Spotify) now adopt the sidebar that already was present in Facebook app (screenshot is from Spotify for iPhone):

1. AFAIK, this is not a standard iOS control (I thought it was typical in Android apps), so, are iOS apps showing that sidebar to keep consistency with their respective Android versions? Or is it a new tendency regarding UX, regardless of having both Android and iOS versions of the apps?
2. I'm not sure if the recommendation is, for an iOS app having also an Android version, to try to make them look as similar as possible, or it should be better to keep iOS looking in a way more familiar for its users (tool bars, tab bars...). I've seen that several apps tend to be quite similar for both platforms (Facebook, Spotify, Foursquare), but there are also apps that look different in each one (Evernote, Dropbox?).
3. Regarding such sidebar control, where can I find a free, easy to customize, and allowed for commercial apps one?

Thanks!

Answer 1

Or is it a new tendency regarding UX, regardless of having both Android and iOS versions of the apps?

It is a great solution for having more than 5 (bottom bar) menu items available. The slide-out menu means you don't lose track of where you are, a problem when accessing a menu through pagination. Since most apps use a fixed header at the top of the screen, the menu is always directly accessible.

I'm not sure if the recommendation is, for an iOS app having also an Android version, to try to make them look as similar as possible, or it should be better to keep iOS looking in a way more familiar for its users (tool bars, tab bars...).

What is more likely or more common behavior: a user accessing the same app on a number of similar devices, or a user accessing a number of apps on a single device. For a user to learn how to use an app, they're mostly helped by experience with other apps on the same platform. Especially with regards to where to find options or certain actions, or how navigation works. Therefore both iOS and Android try to create a consistency that enables users immediately start working with new apps without too much of a learning curve.

So, in terms of controls, layout and navigation, stick to the platform guidelines. Create consistency between platforms with your visual style.

Regarding such sidebar control, where can I find a free, easy to customize, and allowed for commercial apps one?

Can't help here... Google? :S

Answer 2

My opinion is that there are a number of different reasons for the 'trend' (I've seen this used in some very old applications before, so apparently it is popular again). Interestingly enough, before everyone had wide screen monitors, there were different strategies for hiding information, and this was one of them. I think many designers struggling with making the mobile website and web application experience consistent also found this a good strategy to solve some of the problems with the mobile phone screen space.

I would hesitate to suggest that there is a best practice or recommendation, but if you are looking to design an app from scratch, it is certainly easier to try and adopt a similar look and feel if the application doesn't rely on too much of the native OS support and features, otherwise from experience there are a lot of trade-offs if you veer from the native implementations. For existing applications, the issue is to assess the impact on the user by changing the interface design, but generally app users want the best experience, so you should let the users guide you on this matter (as good UX practitioners would).