In terms of development time, iOs and Android both take the same amount of time if the developers are familiar with the platform, as mentioned by andymcsherry. We often develop features for both iOs and Android alongside and usually release on the same day. As far as SMS/MMS integration goes it can’t be compared, but I do agree with the article that its non trivial to integrate with. I have had experience dealing with SMS on android and there is no documentation at all. The only way to get things working is by looking at the source code of the Android sms app or finding snippets on the internet.

I have developed for both platforms and have written a detailed description comparing UI design, Tools, Documentation etc. for both platforms here: http://qr.ae/v4rT2.