Yes, gcc-Lab is completely free and it doesn't have any in-app purchases or subscriptions.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
gcc-Lab is free.
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The app is indeed very useful to me as a Fortran user. The problem encountered in the app is that the source files and executables are not static and are erased every time you boot the app. This creates a difficulty in using the app. If this problem is remedied then the app deserves 5 stars and more.
