FCA authorisation/registration application is a subject best assisted and supported by regulatory consultants. If you are attempting the process yourself, you will need to fully understand the requirements and definitions. The worst thing you can do is listen to those who think they know what is involved.

FCA authorisation Key documents that any firm will need, apart from the application and individual forms from the FCA Connect system are
“FCA Payment Services and Electronic Money – Our Approach” https://www.fca.org.uk/publication/finalised-guidance/fca-approach-payment-services-electronic-money-2017.pdf, Version 4 June 2019,

the PSRs 2017 http://www.legislation.gov.uk/uksi/2017/752/pdfs/uksi_20170752_en.pdf and the Guidelines on the security measures for operational and security risks of payment services under Directive (EU) 2015/2366 (PSD2)

It should be noted that the FCA handbook refers to “Common Platform Firms” and that the common platform requirements (SYSC 4 to SYSC 10) apply to ALL Firms, even if designated as an “Other Firm”. “Other firms” mentioned in some regulations in the FCA handbook may not apply to as a “Rule” to your app directly, as stated throughout the handbook, however there is an expectation that where “Other firms should take account of the critical functions rules as if they were guidance (and as if ‘should’ appeared in those rules instead of ‘must’)”, Firms are expected to follow in a relevant and proportionate manner. Please bear in mind that there are specific rules that are applicable as rules, as explained in SYSC 1 Annex 1.3.3G. In most cases, other than one-man bands, it is considered to be ‘best practice’ to adopt the ‘guidance’ as expectations to maintain a higher standard than other retail adviser firms. The term ’should’ is not an indicator that the issue can be ignored.
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