SNP ministers have doubled the amount of public money being spent on Scotland’s vaccine passport app despite admitting they do not know whether the controversial scheme works. John Swinney said that the ￡600, 000 already invested in developing a bespoke mobile phone app would increase to up to ￡1.2 million, after the original version included a series of technical glitches and security flaws.He revealed the increased cost before admitting it was “ impossible ” to say if the scheme, which busines