In reference to Mobile Device Security, what security can be planned with respect to personal mobile phones used by employees in software development environment?
A mandatory security policy in the company that requires all employees to check their cell phones in at the front desk when in the building is one possible measure. This is not popular but then again there is always a trade-off between convenience and security. I know of companies that have put such a policy in place effectively.
If you are concerned that employees could copy proprietary information (source code, etc) onto the storage that is within their mobile phones, you could create a Application and Device Control (ADC) rule in Symantec Endpoint Protection to block them.
Smart phones and Application and Device Control in Symantec Endpoint Protection 11.0(http://www.symantec.com/docs/TECH147791)
Please do elaborate on other concerns! Mobile Device security is an area where I have a bit of experience.