I recently finished an article for Ocean Navigator on our favorite tablet and smart phone apps. It was a fun article to write for a geek like me as it gave me an excuse to buy and try a bunch of new apps. There were a few gems out there, but sadly, most of the apps I tried were either not very useful for our life aboard, or were just totally worthless.
One app I was particularly interested in finding was something that would improve how we do our provisioning lists. Marcie wrote a blog post a year or so ago on provisioning and in it she described the spreadsheet we use to generate a provisioning shopping list. We have been adding to and editing the list for years, and it is now quite comprehensive. It includes not just food, but everything we consume – from canned corn to Band-Aids to sunscreen.
The spreadsheet has a column for entering how many of an item Marcie thinks we will need for an upcoming passage, another column for entering the on-hand inventory, and a third column that calculates the quantity to purchase. The trick is figuring out how much of each item we will need for the passage.
Our upcoming Indian Ocean crossing will take 3-4 months. How many cans of diced tomatoes will we use? How much salt and pepper, how many rolls of tp, and how much flour will we need? Some things can be replenished along the way, but the selection will be limited and the prices higher, so it's best to get as much as we can while we are here.
Marcie has been doing this for a while now, and once she figures out our needs for a passage, she saves the spreadsheet. She now has spreadsheets for passages of several different durations – 1 month, 3 month and even 6 months. When we provision for a new passage, however, the list always requires some tweaking. Our tastes change, the things that are available in different countries vary, and corrections are made. This provision list will be for 4 months, and since Marcie would have to modify the spreadsheet anyway, I thought I would check to see whether there were any great new apps that might do the job better
I looked at dozens of apps. Some were for pantry stocking, some were inventory control apps, some were meal planning apps, and I tried several that were list-generating apps. My conclusion was that most wouldn't be as good as what we were doing now, and I was unable to find anything that would be an improvement on our spreadsheet approach.
I did come up with a few improvements to our spreadsheet, however. I removed the column that Marcie previously used to enter the quantity needed of an item and added two more columns. One of these columns is for an estimate of our weekly consumption of the item. We might use 1 pound of pasta, 1 pound of rice and 2 liters of UHT milk per week for example. It is difficult to calculate weekly consumption for some items, however. A case in point is mustard. We don't use a lot of mustard, but we do want a jar on hand and the other new column is used to optionally enter a minimum quantity for an item. A third addition was to allow an entry for the number of weeks the passage will take. The spreadsheet now multiplies the weekly consumption of an item by the number of weeks, compares this result to the minimum quantity desired, and subtracts the on-hand quantity from the larger of the two. If the result is a positive number, it is posted in the last column, and this becomes the shopping list. It sounds a whole lot more complicated than it is.
One big advantage of this process is that all the entries can be made on her laptop and then the file can be downloaded to our iPad. We have an app loaded, Numbers, that works much like Microsoft Excel. It accepts an .xls file and allows us to modify and edit it. We can take the iPad shopping with us and edit the on-hand quantities as items are purchased.
Now if I can only find an app that will actually stow the 4 months of supplies for us.
If you would like a copy of the spreadsheet as well as the formulae used, email us and we will happily send a copy to you.