How would you see me best fitting into your team? How does design currently work within your company? How do you develop and grow designers? Why do you get up every day to work here? What does the world look like in 5 years if you guys achieve everything you want?

http://designerfund.com/bridge/interviewing-with-startups-tips-for-designers/

The one thing I've learned to ask: What's the turnover like?

I also like to ask if they have a budget for ongoing education (conferences, classes, company reading).

"What would you do if you were given a day off from work?"

If their answer involves doing anything related to their field -- it could be a good sign :)

Study and master their app. Then ask them how they plan to fix all the things you found wrong with it.

I always want to ask about the hierarchy in the company. Do they work as a small focus group on each project or does every decision has to go through a specific boss? I also want to know how they really value UI/UX design. It's kind of frustrated to find out that they react to visual more than interaction design.

As a newbie to the market, I'm not sure if those questions are appropriate to ask in an interview... I've heard that asking questions in an interview is a strategy to show how have you done the homework/research, and what kind of insight you have to contribute to the company.

Perhaps "Why me?", but I don't think there's any secret sauce. It's all contextual IMO.

If it's a product company perhaps you'll want to know more about the motivations behind the product being created. If it's a services company you may want to know more about the clients they service, their process, or how they hope to engage with you.

Seconded this topic. I've been told it's important to have questions, but I often find myself with nothing to ask. My last interview was a 5 hour marathon with about 6 different people. Each pressured me to ask something. SURELY I have questions, they would say. The whole thing was so thorough, if there was anything I didn't know - I didn't know I didn't know it. Helllllp

One thing I've always asked is why they are hiring. Useful to know if it's because someone left, or they are growing. Also, ask what the company culture is like, it makes the interviewer think.

Anything you can do to make the interviewer talk is good. Most people like talking about themselves and it generally means you have to talk less. Been on both sides as interviewer and interviewee and it works pretty well.

• How long—intake to launch—did your most recent project to complete?
• Are projects typically on schedule?
• Do you outsource work or work with other contractors?
• Do you pay for employees to go to conferences? Do you pay for work-related educational courses?
• Does your company or its employees participate in or sponsor any industry or local design events, conferences, etc.?

For web design:

• How do you test browser and device compatibility?
• Do you use any front-end frameworks? SASS? Node, Grunt?

Maybe companies get annoyed with this but I always ask about if there's a lot of overtime or if there's an expectation of overtime. I also ask about benefits, if it's possible to move up the ladder, etc.

Companies what to know you are invested. Especially with designers. We are a flighty bunch and they want to know you are going to stick around for even a minute.

Ask questions that are about the company. What they are trying to accomplish, stability, vision, how design plays a key role in the companies future.

It's about asking questions that show you are interested in them, not just a paycheck.

I've asked and will ask future employers about their design processes, biz dev process, hierarchy, what my role could grow to be, etc. Stuff I don't want to be (negatively) surprised by in the future. Most importantly, questions about diversity in the workplace! I'm reminded of "Do something useful with those recruiting emails”.

I always make interviews personal. I want to know about the people that work there, what their experiences are, where they come from, etc etc.

Of course, you keep it professional. Their beer of choice might be worth to take note of, but it's not something to discuss at length. Their professional histories, their strengths and weaknesses, their favorite apps, (etc) all of those tell you something about them, and the company they work for.

Companies are made by the people that work there. Talk to them. They'll remember you for it.

.edit:perhaps I should make mention of this: I've never had a bad job interview. Sure I've had ones where I didn't end up getting the job, but they've all been pleasant experiences where both parties learned something.