If it is your first time learning to build android project, you may find an issue when try to generate a private key. This message keytool is not recognized as an internal or external command, operable program or batch file. may occur if the path of your java sdk has not been set globally.
There are two options you can do, the first easy option is by set the path of sdk java globally so you can run any executable file from the bin java folder. Click the window button and type in Environment Variables in the search program field bar.
A popup window will appear, there will be a button called Environment Variables.
Click this button and look for the Path value in the System variables panel and then click the edit button. Enter your java sdk location at the end of the path value. Once you add this you should be able to use the keyword keytool.exe. For example the path of java SDK install can be like this.
There will be a list of path entered this field, so make sure before you enter the path for the java sdk you enter a semicolon first.
The second option is to directly point the path of the keytool to java sdk installation folder, which in this case would be: C:\Program Files\Java\jdk1.7.0_79\bin.
Hopefully this helps for everyone that want to try developing mobile using Ionic and Cordova.