I work with many CEOs and C suite executives as well as "startup CEO" I gotta tell you that the CEO term in our world is becoming less impressive and more egotistical. Most founders want that CEO but aren't really worthy of a CEO title. Just because you launch doesn't mean you should lead much less that you are capable of long term thinking.

Consider Steve jobs who went through this and then had to prove himself to be worthy of such role. If you go with a lesser egotistical title, like cofounder & (___) fill in blank with something you are really useful at.. You can come across as more of a team player, focused in your and your company's efforts... Etc.

I own a web design firm, I call myself owner.
I own and run a hosting and technology it company, I call myself cofounder and chief strategist (not CEO)
I co-own a multistate cleaning company and call myself co-founder and lead marketer.

I had other startups and did also call myself a CEO until I knew better. I read a lot on management, I give presentations for successful leading, team evangelism, gaining competitive advantages, host a series of coaching sessions every year, personally helped several now successful individuals in growing their companies. And even though i have an MBA and all this experience I know that if I applied for a CEO job somewhere I probably wouldn't still get that top role. You must earn it. CEOs has huge responsibilities.
Be a leader and know when you are and when you are not a true CEO or manager for that matter.

Read the Harvard MBA oath and read up on Henry Mintzberg on managing.