Can you suggest an Apple/Android/Windows app to record my content?

There are numerous FREE apps in Apple Store for iPads/iPhones, Play Store for Android phones and in Windows store for Win 8 devices. Simply search in your app store for an app which supports recording in MP3, sharing via email or syncing to your computer and  allows playing the recorded file to review the quality.. Given below are a few apps that we could find using a quick search.. There might be many more.. In no way we are endorsing any of the below apps.. They are given as examples only:
Apple: SceneRecord –Voice Changer, My Memos Free, Voice Recorder Free
Android: Hi-Q MP3 Voice Recorder (Free), Voice Recorder (by lovekara), HD Voice Recorder(by Keerby)
Windows: Easy Sound Recorder (by, Microphone Pro (by MDR Applications), My Voice Recorder (by tsjDEV)

For computers (Mac/PC/Linux), Audacity is a free tool that helps in recording and editing voice. It can also be used to convert other formats to MP3.  You can download it from here. You could use your in built voice recorder in Windows too (You may have to convert it to MP3 using Audacity, though).