Since the link shared here is for Triple N-Back method/app, for those looking for a standard Dual N-Back, there are many web apps, one such app I found in searc

Since the link shared here is for Triple N-Back method/app, for those looking for a standard Dual N-Back, there are many web apps, one such app I found in search results is https://dual-n-back.io/ https://dual-n-back.io/