Well, having an online APL interpreter means there's no need to download one for basic stuff. Also, most APL interpreters are only for non-commercial use (with

Well, having an online APL interpreter means there's no need to download one for basic stuff. Also, most APL interpreters are only for non-commercial use (with a price for commercial use) or not at all free. The only two totally free interpreters I know of are NARS2000 and GNU APL. Last, but not least, ngn/apl has some features other variants don't, for example monadic/dyadic function combination (⍠ operator) and monadic/dyadic D-function combination (one D-function containing ; to separate the monadic and dyadic functions), as well as explicit returns (⍫ function, only usable in D-functions) and infinity (¯ and ∞ literals, as well as their negatives ¯¯ and ¯∞).