The features that matter most are the ones tied to daily work: individual animal records keyed to a permanent ID, health and treatment logs that calculate withdrawal dates, breeding and reproduction tracking, and weight and performance history you can act on.
Tracking breeding, gestation, and calving records means keeping one continuous, dated file for each female, built on a permanent individual ID, that records who she was bred to and when, whether a pregnancy check confirmed she settled, and what happened when she calved.
Yes for record keeping: AgriWebb, Herdwatch, CattleMax's TagMax, Farmbrite, iLivestock, Cattlytics, and My Cattle Manager all document storing entries on the phone or tablet with no signal and uploading them once the device reconnects.
A spreadsheet holds a cattle operation's records well enough until someone outside the operation has to read them, and medication is the usual trigger: Beef Quality Assurance guidelines put seven fields on every individual treatment record, including the earliest date the animal will have cleared its withdrawal period, and every treated animal is checked against that date before it ships to harvest.
For a US herd of up to 1,000 head, published prices run from $0 to about $2,000 a year, and the charging basis moves the number more than the tier name does: CattleMax bills by active-animal band, so 300 head on its Commercial plan is $336 a year with unlimited users, AgriWebb's US calculator returns $720 a year for the same 300 cattle on Essentials, and HerdBoss charges a flat $60 a year at any herd size.