The NRF conference in New York was bigger than ever this year – rumours of 27,500 attendees were circulating on the Tuesday against 25,000 last year.

The size of the event gives a sense of how seriously Americans take retail, and several keynote speakers repeated the figure of one in four US jobs relying on the industry.

The conference’s size is both an advantage and a disadvantage. Entering the technology exhibition is a daunting experience – finding the way out again can be a significant challenge – and discovering the bits of the event that are useful is no small task. Some of the keynotes are interesting, such as Walmart boss Bill Simon’s talk on Tuesday, when he touched on the challenge of competing with Amazon in the coming decade. But many of the periphery talks, of which there are probably around fifteen at any one time, are hit and miss.

Some are hidden gems – one sparsely attended basement discussion, for instance, included Monsoon and Accessorize founder Peter Simon talking about how he built the business into a global player. Others, meanwhile, miss the opportunity to provide the audience with something useful, and instead bore them with a sales pitch.

While its size might make the conference hard work, key trends are still easy to pick up. Some themes are repetitions of previous years – channel convergence, mobile, data – but there are one or two new ideas. The concept of allowing staff to bring their own mobile device to work and get access to work systems on them has come up a few times, and Tesco is one of the first to act on it – chief information officer Mike McNamara said the retailer’s new internal social network will eventually be available on staff’s own mobiles.

Mobile payment has become a bit of a contentious topic, with retailers and consumers failing to move as quickly as manufacturers would like. While the vendors insist retailers will need to invest in a range of services, retailers are unperturbed, at least in the short term  – with consumers hardly clamouring to pay on mobile, sales won’t be lost if near field communication isn’t installed. Instead, retailers are experimenting to see what works for them. This is one area where progress will continue at a fairly steady pace for now – no-one knows which service will emerge the winner or what the tipping point into fast uptake will be, but it doesn’t seem to be here just yet.

Entrepreneurial services like US mobile payments platform Square – not yet available in the UK – and online retailer Dollar Shave Club reared their heads often enough to remind retailers that the game changers of the past decade have been small, internet-enabled services that have touched a nerve with consumers.

Another big theme was ease and convenience. New players – as well as Amazon – make this their point of difference, and all retailers will need to put this at the centre of their operations. As BT futurologist Nicola Millard said at an innovation showcase, shoppers will increasingly only show loyalty to retailers who make things easy for them, and that might be the best lesson to learn from NRF this year.