...or apps for system admins, privacy nuts, and hackers. When I first got my Droid 2, I started looking for applications right away that would turn my smartphone into more of a handheld computer. This meant I needed to find tools that would let me establish secure connections with my home server, tools for secure file transfer, and tools for basic network analysis and troubleshooting. This led me to a bunch of interesting applications along the way, from which I’ve compiled this list of tools for system administrators, security freaks, and the everyday hacker. The Nerd Necessities Need to poke a hole in a pesky, restrictive firewall? SSH tunnel. Need to download that AVI you forgot to transfer from home for the flight? SFTP. Want to connect to that shared folder on the public hotspot labeled HOTPIXXX? You shouldn’t do that, but SMB could probably help you out. These are essential tools for power users. Tools that make interacting with networks and connecting to remote services securely possible from your Android phone. Connect Bot Connect Bot is a full featured ssh client with support for tunneling, pre-shared keys and the like. The app also allows for a local shell so there is no need to download an additional terminal client for your phone. I use ssh all the time to run HandBrake-CLI on my server and convert DVDs I’ve already backed up to Android-optimized video. It’s still the standard for interacting with machines remotely. Wyse PocketCloud Free RDP/VNC I don’t personally use RDP/VNC, but a lot of people still do. There is a pay version of this client, but the free version supports most things other than encryption. However, setting up an SSH tunnel in Connect Bot and connecting to your local VNC server through that is probably more secure anyway. There's also a simple android-vnc-viewer app for just VNC. Astro Astro is hands down the best file manager for un-rooted Android users. It sports sftp support with better encryption speeds than any of the other sftp clients out there. Also, you can download an SMB module that allows you to interact with Windows shares. Astro is essential for just tossing quick files around a network. The only thing that could make it better would be a dual-pane interface in landscape mode. Better Terminal Emulator Pro If you are a long time Linux user you probably feel comfortable doing a number of tasks from the command line. If you want to be able to throw together shell scripts for accomplishing small tasks, Better Terminal Emulator Pro comes with the bash shell and BusyBox, extending the command line on your Android device quite a bit. It also comes with a great terminal emulator for interacting with your Android phone. The price is worth it, in my opinion, for anyone who feels more comfortable in the shell. Better Terminal Emulator Pro also comes with ssh. Nethack I hope you didn’t think there was actually a Linux-based device on planet earth without a nethack port. I really started to enjoy the nethack port for Android after I figured out that tapping in the edges of the screen was how you went in certain directions. Before that I was using the numbers at the top of the Droid 2′s physical keyboard. Don’t make my mistake. Oh and if you get caught with it at the office, just tell your boss you’re pushing packets around the network. Works every time. Oh and of course, there’s SLASH’EM too. Network Monitoring and Information Gathering I tend to look for tools when I have a use for them so this collection is far from complete, but I feel that a lot of the basics are coverd here for quotidian data gathering for troubleshooting, analysis, or whatever you want to do with it. Shark for Root This is a port of WireShark for Android and it only runs on rooted devices. You can use it to capture packets on a network you are connected to. Unfortunately there is no live viewing, but you can use the app Shark Reader to review the capture files after your capture is complete. WireShark is one of the best ways to discover and monitor problems on your network. Network Monitor Network Monitor is a good way to make sure that essential network services like ssh or https stay running. The application pops up with a notification wheenver one of your online services has gone down, allowing you to react quickly and have minimal downtime. Net Status Net Status is a collection of network tools for, well, checking your network status. It has a ping tool, netstat, netconfig, and can display the current ARP table. The most recent update also allows you to scan your local domain to find all of the other active hosts on the network. Basically, it’s an essential collection of tools that would normally come with most installations of Linux. Nmap Nmap is the classic port scanning application that sports OS fingerprinting and more features than most people can remember. Click here for the reference guide. Wifi Analyzer Wifi Analyzer shows a wealth of information about any signals within range of your Android phone. You can find the best channel for your access point, see channel graphs with strength overlays, and see a dBm meter for hunting down the location of access points. It’s an awesome, information-packed way to find the best spot for connecting to an open network. Wifi Tracker Wifi tracker is great if you want to view all the open Wifi hotpots in your area on a map. Wifi tracker exports all of the hotspots to a KML file that you can later use to view all of the data in Google Earth. It’s a really good way to map a big network for coverage, such as on a university or corporate campus. Net Tools Net tools is a networking toolkit that provides a pinger, a DNS to IP lookup tool, an HTTP header downloader, and netstat. It’s a good tool for performing some quick lookups, but most people will find the HTTP header downloads to be the most useful. Privacy Whether you want to anonymize your traffic to hide it from your boss, chat with weirdos in onionspace, encrypt every message on your phone, or just hide dirty pictures from your mom, privacy is important when you use a device that is constantly connected to a public network or transitioning between secure and insecure networks that you may or may not own. Orbot: Tor for Android Anyone who wants to fully anonymize any of their application traffic needs to install Orbot. I wouldn’t suggest spending too much time in onionspace since you might find yourself ripping your eyeballs from your skull, but the darknet does have its use for keeping some communication private, especially when using Wifi networks you don’t own. However, you might want to consider an SSH tunnel or secure VPN before using Tor since it’s incredibly slow. The best part about Orbot is that you can just select certain applications in its settings. It doesn’t blanket your entire system so you could potentially install an additional browser and use that purely for Orbot. IP Address Widget & App This app’s widget will sit on your home screen and will constantly display your IP address. If you spend a lot of time bouncing around between proxies you can use this app to make sure they are actually working. APG APG is a near fully-functional PGP port for Android. It integrates with the popular K-9 mail client so that you can send encrypted messages. You can also copy encrypted text to the clipboard, so you can use encryption elsewhere, if inconveniently. imgur for Android I hesitated adding in an imgur app, but one of the best features of imgur is that it strips the EXIF data from uploaded images. There are a number of imgur apps, but this one is by far the most feature filled. If you want to keep someone from knowing your location from a photo or that you took the photo on your Android phone, this is a must before you send the photo to them. Vaulty If you ever take photos that you want to immediately hide, you should probably download Vaulty. Vaulty lets you hide items simply by using the share feature. It’s a quick and easy way to get rid of those images of all that police brutality you just witnessed, or all that stuff you don’t want mom to see when she is flipping through your gallery page. PhotoGeolocator PhotoGeolocator allows you to change the geotagged location of any photo. This is pretty useful if you want to do a quick scramble before sharing the photo or if you want your friends to think it’s snowing in Hawai’i. Now if only someone would develop an application that stripped the EXIF data from a photograph using a simple share feature. Let me know either by e-mail, or by commenting in this thread if you know of any more necessary apps for the super nerd. Thanks for all the information you've all contributed here. It's helped me have a lot more fun with a phone than I probably should be having.