PeekIt is intended to examine and even change file contents. The application has a simple interface; however, specialized knowledge is definitely required in order to understand and modify the values shown. Luckily, you can open various windows to examine multiple files simultaneously.
When you open a file, you can view two different representations of its contents. There is the left pane that shows the raw data without filtering. On the right, you can explore the same data but as hex values. It is quite convenient that both panes scroll simultaneously, which ensures both views are synchronized. However, it is possible to hide the Hex pane whenever it is not necessary, which gives you more space to work with the raw data.
It is good news that PeekIt allows annotating files. For instance, it lets you write notes about specific locations within the data, which favors collaboration. Moreover, the risk of the original file being involuntarily rewritten is minimized as it supports two modes: Read Only and Editing. Thus, to modify the contents it is required to press the Modifiable button. Another advantage of this tool is that it supports opening large files without straining system resources as it only loads their contents part by part.
All in all, PeekIt comes in handy when you need to inspect or modify the contents of any kind file even when you do not have the proper application. Likewise, it comes in handy to make quick fixes without needing to recompile the whole file. The product is free but, unfortunately, it is being discontinued, which means that it will eventually cease to be compatible with newer macOS versions.
v2.6 [Jun 9, 2010]
Fixed a bug with loading and saving formatters on launch and quit.
Fixed a weird bug in the byte string formatter.
Fixed a bug where the byte string formatter wasn't respecting the Hex checkbox, it does now.
