iPhone App unsupported functions

I am using an iPhone App called DocsToGo that I can synchronize with my PC, unfortunately the below two formulas have a functions that are not supported by my iPhone App. I believe it is “EOMONTH”.

The following link has all the supported function of my iPhone App.
http://support.dataviz.com/support.srch?DocID=2310

Help please in modifying the below two formulas to include a supported functions from the link above.

=IF(MONTH(DEC!G58)=MONTH(DEC!H58),"",DEC!H58-EOMONTH(DEC!G58,0)-1)

=IF(MONTH(G3)=MONTH(H3),H3-G3,(EOMONTH(G3,0)+1)-G3),"")

Please refer to your application's documentation or site - Thread closed