Well, most people in the states use iPhones. I guess that was the reason they had a start with the IOS App release first. But it doesnt matter anyways. Its just the beta version. The full version of the app wouldnt be released still later this year. Both that of Android and iOS should be ready then.
Well that I don't know much about but I think a good number of people (if not most of the community members) in dreamr's platform uses android too. Personally, I do think it's better to work towards releasing both same time
Theres a lot of arguments about what operating system has most users or is widely used. And developers sometimes have to decide if Android or iOS users gets to get a feel first. I think every project should make a decision based on market data. Dreamr must have had a look at the statistics and made a decision to launch both.