Non of these 'offerings' properly represent the legal CAA chart (if you're flying VFR in the UK). The only solutions available that I'm aware of that meet this requirement without also carrying a paper chart (and at £16 a year, why not?) are either Memory Map or Airbox. I'd be interested to hear different. I asked at the Skydemon stand at the Flyer show if it would be possible to have the CAA chart incorporated and was told an emphatic 'NO'.
With Part.NCO.GEN.135(a)(10) in place it is questionable whether paper charts do comply fully, as it is set that the aeronautical information has to be recent on the AIRAC cycle - which paper is usually never. Part.NCO did bring the clear commitment to electronic charts and EFB, but may have killed paper charts by that. One more question, how do you determine "legal" as a parameter for a chart? Regs don't say anything about charts being required of any kind "legal", just appropriate.