I found a number of these "pay by space stations" around the farmer's market. Thought I should make mention of them as they go into use today. Not sure if they are located in other areas of the city or if they are just a test project.
The main parking lot west of the farmer's market is still free I do believe. Most days this lot is fairly full of what I can assume is downtown workers.
I checked the city's website for more information regarding these but had no luck.

^^ Found one that appears to by solar powered.

^^ Solar Panel
While checking out the city's website I did find out that the first time use of a cell phone for parking is free.
Pay-By-Cell Phone At Parking Meters
An option to pay for metered parking with cell phones is available in the Broadway area, the downtown core and all City of Saskatoon metered parking lots. This electronic parking payment system (TM) is provided through a partnership between the City of Saskatoon and New Parking Inc.
Each meter in this program has a sticker with a four-digit meter number and a phone number. To pay by cell phone:
Call 955-9969
Wait for the prompts
Enter the four-digit meter number
Although the meter will not indicate it, the vehicle will be legally parked for the maximum stay. Enforcement Officers carry wireless pocket PCs in order to identify which meters have been paid for by cell phone, and how much time remains.
To stop payment, call the phone number again. Make sure you use the same cell phone you had used to initiate payment. You will be charged for the amount of time used, in 30-minute blocks. If a call isn’t made to stop payment, the maximum time at that meter will be charged.
Charges for parking that are paid by cell phone will be sent in a separate statement from New Parking Inc. No parking charges will be included on cell phone bills and there is no extra charge to your cell phone to use this service.
All cell phones will work, regardless of the mobile provider or the technology it uses.
The first time this service is used, it is free. Shortly after the first use, New Parkng Inc. will contact the cell phone user to register payment options for future use, including credit card, prepayment or PayPal (online payment).
On-line registration for cell phone parking is available through
New Parking Inc.
Source