It’s easy and fun! Take as many overlapping pictures with your iPhone as you like, add them to AutoStitch Panorama and tap “stitch”. The App takes care of the rest (rendering is pretty fast) and crops the final result to a perfect picture. Really the best way to create impressive panoramas on the go if you ask me. $1.99 well spent!
Stitch together several overlapping pictures and create beautiful panoramas with Hugin. It’s not the most user friendly software on the planet, but offers many possibilities once you get the hang of it. Hugin is open source and there’s a good selection of tutorials on the official website.