Pamn IP Scanner (or PIPS) was formerly titled "Nmap for Android." Fyodor, the inventor of Nmap, asked me to change the name and icon to reduce user confusion. This app is simply a wrapper around a cross-compiled Nmap binary built for your Android phone.
Source available at http://nmap.wjholden.com/src/ in accordance with the GNU Public License.
Q: I want to run Nmap myself from a terminal. Where are the binaries?
A: The binaries are (usually) saved in /data/data/com.wjholden.nmap/bin/.
Q: Is this a GPL violation?
A: I'm not a lawyer, but I don't think so. My sources are freely available and also licensed by the GPL. You are free to modify and redistribute my code provided you share those changes back, IAW the GPL. Free software is not always zero cost.
Q: Where is the source code?
A: Distributing source code along with Android applications is a bit impractical. Download the source code from http://nmap.wjholden.com/src/.
Q: Wait, you're not Fyodor!
A: This is NOT an official release from http://nmap.org, this is simply a front-end that calls to a precompiled Nmap binary.
Q: Do I need root?
A: No! You can use this program with or without root, although there are a few advantages to having root. I've seen a few problems with -O for Operating System fingerprinting (this would happen on desktop Linux as well). Non-root users will usually need to use the --system-dns argument.
Q: What's up with Atrix?
A: I don't know why, but this program has never worked with the Motorola Atrix, despite extensive efforts toward compatibility.
Q: Is NSE supported?
A: No, NSE/LUA are not supported for now, but it's definitely on the radar for a future revision. Some command-line arguments will not be available until then.