can i update an app in the market without incrementing the version?

Periodically I'd like to make very minor changes to an app on the market, that don't justify notifying users that they need to upgrade. For instance a li开发者_运维知识库ttle cosmetic tweak. Basically I don't want anyone (including my client, for whom I built the app) to notice that I made the change, but I'd like all new downloads to get the changes. Can I do this, or will making any changes cause everyone to be alerted there is a new version?

I understand where you're coming from but this is a very bad idea. If it were possible you could have a bunch of people with the same version numbers but a different program making it very difficult to track if something goes wrong.
You can however increment only the integer version and leave the text version the same (this only shows in the market anyway).
This will still cause people to get auto updates for your app. I think you should either bundle all your changes up and wait or just accept that everyone will be getting lots of updates for your app.

Unfortunately Prashant's answer is not correct. You only need to increment the code, not the human readable version string.

I frequently leave the user visible version number alone when releasing minor tweaks and bug fixes, saving the market visible version numbering for actual features and major bug fixes.

Well last time i tried to the same thing, i got a message that application version numbers needs to be incremented before uploading a new version of the application. Also, version number and version code need not be in sync. But both needs to be incremented before uploading the new apk in market place. Hope this helps.