"As we evolved, we heard of people with multiple residences who could not keep track of what they had, and ended up buying duplicates," says Doug Greenberg, vice-president of Garde Robe. "Our other clients treat us like a luggage-free valet service, the hub for their wardrobes. Everyone uses it differently."

Garde Robe, which has branches in Los Angeles, Las Vegas, Orange county, San Diego, Florida and Tokyo, is preparing to open in London and is scouting partnership deals in Hong Kong.

The service has a simple set-up. Clients need to meet a 50-garment minimum, which are stocked, alongside 10 pairs of shoes and a large box for accessories, in one of the company's international storage facilities, which, according to Greenberg, have been outfitted to museum-quality standards.

Every item is categorised and archived through a virtual closet. If a customer in, say, New York, is making a trip to Hong Kong and would rather not pack a bag, she will let Garde Robe know which pieces she wants, and the wardrobe will be waiting at the hotel or home upon arrival.

The service costs US$7 per garment, per month. Shoes and accessories are complimentary.

"It satisfies a lot of different needs," Greenberg says. "We had one client who was on a two-year, round-the-world trip so we sent his things on to New Zealand, Southeast Asian countries, just about everywhere."

After use, the clothing and accessories are put into pre-labelled packaging and returned to Garde Robe.

"For a lot of people, this represents the ease of not having to pack, or go through customs, or deal with dry cleaning and keeping track of things," Greenberg says.

Boris Pevzner, the founder and president of Collectrium, a cloud-based art-inventory management system for private collectors, says his app has basically replaced written lists.

"I'm a collector, my friends are collectors, and we were all looking for a solution that allowed us to access our collections any time, anywhere, in a way that was secure and private," he says.

The art management aspect of the app, which costs US$35 a month, is now used by more than 100,000 collectors worldwide - about 20 per cent of whom are in Asia. It is also used by 4,000 galleries and by all major art fairs.

"Many of our customers have multiple homes in multiple continents," Pevzner says. "Their collections might be spread around residences."

The service allows for an unlimited number of artworks to be managed. High-quality photos are uploaded and information is input, available in a number of languages (Chinese and Korean are on the way).

In June, another service, Trov, started up. It is perhaps the most comprehensive tool for the super-wealthy who need to manage their homes, speedboats, jets and other toys.

"We recognised that about half of the world's household wealth is made up of tangible assets," says Mark Dowds, executive vice-president of business development for Trov.

"Managing a portfolio where an individual is building wealth quickly can be particularly challenging. Very often people don't know what they own, where it is or what it's worth. So we … help them manage it all centrally and easily."

Dowds says that the business has grown so rapidly that "it is like riding a rocket".

In the past 10 years the number of wealthy individuals has increased globally and there has been a shift towards purchasing and investing in tangible assets such as property, instead of traditional liquid assets, he says.

Trov's clients tend to have a minimum net worth of about US$10 million, although many are multi-billionaires.

Once they sign up, a Trov "concierge" is sent to their homes or elsewhere and inventory is recorded, at US$2,500 a day. All possessions are itemised and when the information is collected, it is securely uploaded on to a privately accessed site.

A digital rendering illustrates the layout of the home, each room and its contents, with a photograph and brief description of each item. Other information can be included, such as receipts for each purchase and insurance information.

Today the majority of Trov's primary business is US-based, although it plans a British opening this month. Dowds says the service may also expand to Japan and that China would most likely become a primary market eventually.

Information is constantly updated so those who sign up for the service know where everything is, all the time. After the initial data collection fee, having access to the software costs US$100 a month.