System voltages: Can I use a 5V touchscreen shield on a 3.3V arduino? The system voltage on my arduino 101 is published at 3.3V, even though it also has a 5V output pin. 

My Seeedstudio touchscreen is supposedly a 5V device. http://wiki.seeed.cc/2.8inch_TFT_Touch_Shield_v2.0/

I believe I've successfully ported the library for this touchscreen to the 101 because it now runs and compiles on both the 101 and the Mega, although it gives erroneous values on the 101. Could it be because of this voltage difference? is there any way to fix it?

Edit- I should add that the 101 is labeled as "5V tolerant".

Edit II: I've found a pretty informative review that explains a little bit about how the 101 is supposed to work with 5V peripherals. I'm not sure though how it could work in cases where a shield does not recognize 3.3V as logic high. Usually 3.3V is right around the cutoff voltage for many circuits. http://www.tweaktown.com/reviews/7706/intel-curie-based-arduino-101-programmable-microcontroller-review/index2.html
You'll probably need a fairly common device known as a logic level converter.  One such example, in breakout board form, can be found here: https://www.sparkfun.com/products/12009

There are tons of other options depending on what exactly you need.