We believe the options listed above are the best wireframe tools around. They're all solid, highly recommended options that can allow you to create robust wireframes for your designs. Which option is best for you depends on your experience and on how you want to work.
If you want a tool specifically for wireframing with special features intended for the process, you'll probably want to go for one of the dedicated wireframe tools. If you're a newcomer with little experience, an intuitive, relatively simple interface like that of UXPin, Balsamiq Mockups or Justinmind may be the best choice here. However, if you're an experienced UI or UI professional you may prefer an option like Azure RP.
Meanwhile, if you'd prefer to use just one app for the whole design process from start to finish, rather than switching across different software, you may prefer an all-round design tool like Adobe Photoshop, especially if you're already familiar with the software.