Real-time location on inventory is available today, and I believe it will soon be the status quo. Handhelds are still the prime inventory tool; I do not mean to imply that they are being replaced, but I do expect them to adapt to the changes in technology. It is not hard to find articles that compare handhelds and always-on location, but I think the more interesting question is, "How can they work together?"
Today, many handheld applications live entirely on the device; there are some good arguments why this is done, but in the very near future, these approaches will become cumbersome. Devices need to connect and share data, which is the entire backbone of the IOT world so many subscribe to (myself included). Handheld technology will change to meet the approaching tide and in doing so, become a tool we use within an always-on environment.
As good as always-on location may become, it will never replace the need for physical audits, human eyes on a product or asset, and verifying condition as well as other variables. These audits will remain a handheld application; the handheld form factor may change, but effectively, it will be the same premise. This is also true from retail checkout to asset checkout - these are proximity events that change the condition of an item and are handheld events all the way. However, what always-on location brings to the table to assist in those tasks is still being recognized, and, even counting only the currently developed solutions, these benefits are big.
As we advise clients on how to think about inventory, location, tracking and transactions, we highly recommend a flexible strategy that involves the ability to shift the workload to always-on but maintain handhelds of localized activities.