For your first question on Stack Overflow, it was one non-moderator user that voted to close. You need either 5 people or <5 people and 1 moderator. The person who voted to close was not a moderator - if it was a mod that voted to close, the question would be automatically closed. I would not worry about your question being closed - it was either a mistake, a confused user, or someone who doesn't understand what is allowed on Stack Overflow. If the question does actually get closed, come back here and I'm sure you can get 5 people (or a single moderator) to reopen it as it is indeed appropriate for SO.
As for the second question, it's not appropriate for Super User. Phones and other similar devices are off-topic, regardless of the question. SU is for questions relating to software and hardware of personally-owned desktop and laptop computers. Your question about iPhone web apps does not fit that category and would best be asked on Stack Overflow (it is development related, specifically getting your application to the end user) or an iPhone developer's Stack Exchange (I don't think one exists yet, but I'm not an iPhone developer, so I'm not sure).
The very first question in the Super User FAQ explains why your question was closed:
What kind of questions can I ask here?
Super User is for computer enthusiasts
and power users. If you have a
question about …
- computer hardware
- computer software
and it is not about …
- videogames or consoles
- websites or web services like Facebook, Twitter, and WordPress
- electronic devices, media players, cell phones or smart phones, except insofar as they interface with your computer
- a shopping or buying recommendation
… then you're in the right place to
ask your question!
Please look around to see if your
question has already been asked (and
maybe even answered!) before you ask.
It's also perfectly fine to ask and
answer your own question, as long as
you pretend you're on Jeopardy: phrase
it in the form of a question.