LCD and Arduino which to use?

I need to connect an LCD (2.5'' or more) with my Arduino ONE and must to be possible to communicate with I2C

Which one lcd is better to buy?

the priory are:

1)the price 2)the simplicity


Color LCD Shield sparkfun color LED shield is controlled through SPI interface.

I have the Devantech LCD03. It's a 4x20 with a backlight. Display quality is good. It's not a graphic LCD but you can create custom characters for simple graphics. I searched here for code and it worked right away. I am not sure I would call any I2C code simple, but the sample did not require much in the way of changes for my purposes. It's around $50 or so quantity 1.

Oh yeah - be sure you have a good reason to eliminate using NewSoftSerial and a serial LCD; that would give you more choices and would only require running 3 wires (-, + and Tx) instead of 4. In retrospect, I really didn't have a good reason. I won't change it since it is working and I have plenty of things that need work.

If price is the most important priority, I think the best choice would be a nixie display. Those are the most expensive displays I can think of. There are also 7 segment VFD tubes, which, if combined with a separate controller to provide SPI or i2c, should also come out to be quite highly priced. Alternatively, an industrial surplus shop may have an old train station display with those clacky-clacky flapping-down leaves that form letters.

Cheapest solution is:

LCD ~ $7us pcf8574a ~$1us

This makes your lcd i2c

There is code in the playground to drive this, however I recently rewrote it in such a way as to be a LiquidCrystal drop-in replacement.

I will post this soon.