Show multiple GPX files

[PedroF20]

Is it possible to show an entire folder of GPX files in one map, instead of showing just one GPX?

Also, is it possible to dynamically remove and add tracks, depending on the date I pass to my function?

[mpetazzoni]

Just add multiple GPX layers to the same map. You can dynamically remove and add layers to a Leaflet map, so this also answers your second question :)